You are welcome :)

So, to sum up and clarify, are you saying that in your example, the left hand image in each pair is the one interpolated in the raw conversion, and the right hand image in each pair is using your regular step interpolation in CS? The difference is certainly marked. I wonder if the same difference is there with downsizing

FYI it is commonly accepted that stepped interpolation is not the best method, especially for relatively small upsizing. It is reckoned to be best to do it in one go using bicubic interpolation. Again I have never compared the two methods.

LOL well you are all welcome to it :D I suppose someone has to do it though, and it can be interesting to see the results. The thought of photographing fonts and colour charts however is frankly a bit a bit of a *yawn ;)

Yes Stephen it is the left hand one that was done with your method and the right with just an image resize going up by a 100 pixels each time with bicubic until I reach the same size. I will edit the other to point out which is which.

The font and colour bars had nothing to do with photography. Look no camera hidden up my sleeves :rolleyes: It was to illustrate how jpeg works as there are many misconceptions with regards to the subject. But I do take your point I'd much rather be out snapping away. Lets hope these dull gray days are soon behind us.

:D

Someone has though. After a similar discussion on DPReview Calvin Hass posted this comparison

Raw shooter now installed but it may take a while for a result .......... 72 page manual ;)

One benefit I suppose is that it forced me to do the SP4 upgrade and that took a while.

Don

2 RAW converters in action
 

I have downloaded Rawshooters Essential to be able to look at the effects of converting an image from RAW using more than one converter.

Initial impressions of Rawshooter is that it is seriously fast in comparison to Nikon Capture v3. As mentioned in my previous post the manual is 72 pages long so a bit of playing is required. It has far more features than Nikon Capture v3 and appears to offer some of the features mentioned in Stephens earlier posts.

As I do not have many RAW images but I have found one that I has a range colours in a small area to show any effect on the image through RAW to JPG conversion.

NO PROCESSING OTHER THAN CONVERSION HAS TAKEN PLACE ON EITHER IMAGE.

The composite has received 15% compression to post it here.

Early days with this program but the results are way different.

Relative file sizes : Orig RAW 9.11mb Nikon Capture converted JPG 5.73mb Rawshooter converted JPG 3.46mb

Don

I am not a fan of RSE and the above composite enforces my view. If you own a Nikon and shoot RAW NC is the quality way of converting RAW to Photoshop for further processing. NC is slow compared with others but worth the wait.

From this comparison I would agree Foxy Bob.:)

A pertinant question may therefore be do say Canon, Pentax etc offer their own converter ? There seems to be more going on in the conversion than is immediately obvious.

Perhaps we need a techie to explain.

Don

Well I'm sorry but I can't really see a great deal of value in Don's comparison. Please don't misunderstand me I have no loyalty to RSE whatsoever, but the same comments would apply whatever programs were used. How can you virtually dismiss RSE on the strength of a test which as I understand it has simply used the default setting within the two progs.

Surely a test would be better served if a file was adjusted to ones personal preferences. To me for example the RSE version is slightly warmer than NC. Maybe there is a tad less contrast. However its not my image and I don't have an idea in my head of what I would expect it to look like. Indeed another person may like the RSE version better, that would be down to personal likes and dislikes.

The point is though that had you used ACR in CS2 it would have applied different default settings and the image would no doubt look completely different. This default setting scenario is surely not the issue though. RSE like NC, C1, ACR, and Bibble all have the abilitiy to tweak the images ad infinitum to ones personal preferences.

I personally don't see how we can say from this example than one is better than the other. Just what would the criteria be that would say definitively that one is better than the other anyway :confused:

After looking at the two attachments again in PS I would also comment that the RSE version shows marginally more detail in the blacks, round the barge window for example. Also the full image has some serious compression artefacts, and neither of these are apparent in the browser, so where does that leave us? :)

Stephen,

The full image had to have 35% compression to post here and was only posted to show where the crop came from.

No processing was carried out in order to see the difference in how a RAW converter may affect a conversion to JPG. If you retain your file in RAW format then this is of no concern at all. If however you for any reason convert the processed image from RAW to JPG then the test shows there can be an effect.

That will no doubt lead to another question and that is if you have a RAW image do you need to convert it to JPG at all ? Why would you ?

I'll start the list

Passing a copy to a friend.
Posting in a gallery on the web.
Smaller file size for printing at home .

In each case the image you spent time on, getting just right, may not in converted form resemble it. Compression for e-mailing / web posting will have some effect but I suggest not that much.

Don

I wonder if you are missing some of my point Don. The fact is that of course some processing has gone on. This is proven by the differences I mentioned in the two examples. However at their default setting there is always going to be a difference between progs. I suppose the same as there would be with an jpeg image out of different cameras. Part of my point was though that your example does not really show that one is better than the other, only that they are different. You cannot say from this test that NC is better than RSE.

I hope I'm not misunderstanding your comment 'if you retain the file in Raw format' This should always be retained, its your neg.

To do anything with your image you need to process the Raw file in the converter, however you decide how it looks finally. Even for web use though the image may look different especially if you use Adobe RGB. All browsers default to sRGB and this will show up on the web.

[quote=Stephen] You cannot say from this test that NC is better than RSE.

QUOTE]

Stephen,

May be my fault re NC and Nikon. It relates to the converted image in comparison to the adjusted RAW. The NC version when placed side by side with the RAW shows almost no difference in lightness/tone. To acheive the same result with the RSE would have required a tweak or two. The amount of adjustment would be as you can see from the comparison.

As a converter I am not saying that NC is better than RSE in any other respect. As I mentioned RSE is very fast by comparison and has far more tools to allow for image adjustment. It would take a lot more use of the program to establish a better one. Anyway that may not be strictly a fair test as my version of NC is from 2002 and RSE is 2005.

I will use RSE with its advantages to play with the various adjustments - good for the learning curve.

[ Quote : I hope I'm not misunderstanding your comment 'if you retain the file in Raw format' This should always be retained, its your neg. ]

Once again I may not have put this as clearly as I might. I was not suggesting that after a conversion to JPG, if you made one, you bin the RAW.

Don

After 3 hours of playing with RSE this image is an pretty fair reflection of how far I have got.

I think getting exposure right is a lot easier.:D

Don

Working with RAW files.

My PC is by todays standards of limited power - 800mhz, 128mb ram, Windows 2000pro operating system.

My only experience of RAW has been to use it in tricky lighting situations where W/B might be a problem ie in the hangers at Duxford. Images being then adjusted and converted to JPG for fast processing anything else ie; crops, dust removal etc in PSP7 or 8.

Yesterday I spent around 8 hours playing with a few RAW files and the following are my personal thoughts based on that experience. Two RAW converters were used = Nikon Capture V3 ( released 2002 )and Rawshooter essentials ( released 2005 ).

Doing more than tweaks to exposure or W/B was a fairly painful business due to lack of processing speed. With more adjustments than that, such as those as available in RSE, I found that I was loosing intimate contact with the image and consequently the end results required far more work on the conversion in Paint Shop to get back to the desired result.

Each program had its advantages and disadvantages. Although NC was slower I found it easier to use, and with my lack of previous use that cannot be put down to familiarity with it. Other than a straight conversion of the RAW file I cannot post a comparison, as neither program recognises changes made in a saved copy of the RAW file from the other program. I was not able to achieve a suitably accurate match on a single image with both progs for a comparison of a conversion to be posted.

My conclusion therefore is that to use RAW and not be driven mad by it you do need a powerful PC. With more limited PC resources then using JPG fine with the occasional use of RAW is a more satisfying way to go. A well exposed and not overly in camera processed JPG is still makes a good negative.

So a couple of thoughts for the melting pot.

1) For those with less PC resource the origonal question of in camera processing is still valid.
In these discussions I think it important not to lose sight of the costs of some of this kit, and peoples ability to afford it. Fast PC with large HD £400+ Adobe CS2 £500+. I ask myself the question would any of my images directly benefit from this spend, or have I been in anyway been limited without it, and the answer is a resounding NO. Nice to have but far from essential.
2) A correctly exposed JPG is NOT inferior to RAW. With the very sophisitcated light metering systems now built into cameras how often do you really need, or rely on the exposure compensation of + / - 2 EV offered by RAW.

Don

I reckon you summed things up nicely with those conclusions.

I've quietly been watching this thread with some interest as I only started using raw myself maybe 6-7 months ago ..... with some prodding, encouragement and help from Stephen Anstey (in other photography boards.

I was also using an old Win98 SE PC until about 18 months ago and that struggled with PS7 using jpegs, let alone raw! I'm not a very experienced photographer either, only got started in 2003 with a Canon G3 than got the Pentax istD November 2003 so I felt I needed to concentrate more on learning to use the camera more competently before trying to expand my digital darkroom skills.

When I eventually upgraded the PC I was still reluctant to attempt using raw - but I eventually decided I should at least give it a go and learn how to go about things - then I'd have more choices if I at least learned to master the digital darkroom techniques.

I'm glad I did as it means I now have the choice of shooting in whatever mode might be best for the occasion.

I agree wholeheartedly with those who have said shooting RAW allows you to correct mistakes a little more and maybe salvage a special shot that can't be repeated. I agree whole heartedly with someone, I think it was Tannin, who said you sometimes have to consider the trade-offs and shoot high ISO jpgs for bursts of birds in flight ... something I forgot to do myself a couple of weeks ago and missed several potential Gull shots as I was shooting RAW and the camera/card read/write was too slow so I was having to wait too long between bursts.

I also agree it's an expensive business trying to keep up with the latest technologies - both hardware and software.

Its a wide and varied learning curve, lots of choices on all aspects. The most important thing, in my humble opinion, is that everyone should carry on enjoying their kit and their hobbies at their own pace...... and also enjoy sharing experiences, skills and photographs. :)


Pol

I have just spent time on BF and found a thread debating RAW & JPG.

To show that I am trying to steer a middle course on the subject, I am posting a link that was posted in that thread. Luminous Landscape - Understanding RAW.
http://www.luminous-landscape.com/tu...aw-files.shtml

Makes interesting reading. It is information that only a regular user of RAW files can comment on really as a lot seems to hinge on the number of bits 8, 12, 16. I do not have a cache of RAW files that will enable me to see the effect.

Obviously no real comparison pics can be posted as they would have to be JPG which is 8 bit.

Don

Shed Loads of Info on The Digital Image
 

A really interesting link with lots of info on the digital image. http://www.cambridgeincolour.com/tutorials.htm

Don

PS I have now posted this link in the Members Forum as well.

It seems a fairly clear and unbiased article to me Don HERE is another you may be interested in

It seems to me that the biggest thing that is stopping you from becoming a full convert ;) is the lack of a machine with enough power and a prog like CS2 :)

Again there is an interesting article on this site about using Raw.

One interesting thing he raises and I forget whether this has been mentioned here here before is the lack of a standard format by the camera manufacturers. As you may be aware Adobe now have the DNG format, and it is possible to download the DNG converter from their website for free. This will convert your cameras RAW format files to the DNG format. This holds all the data from your files but is a standard file type and in fact creates a smaller file so saving some space. Your camera Raw files can then be discarded as they are superfluous to requirements.

Stephen,

I will come back on this later as I have passed by some info on DNG to get to my next post. Don't throw your old Raw files out just yet.

Don

Another really interesting tech talk on RAW and JPEG. http://www.ronbigelow.com/articles/raw/raw.htm

Don

Dng
 

Stephen,

I think the clue here is to think of who looses with DNG and that will be those Camera Manufacturers that produce their own software and how they will react to paying royalties to Adobe. For example how much money do Nikon make from NC. What of their new tie up with NK and the impending release of Capture NX. I do not know which other camera makers supply their own software. OK a lot of chat about Leica and Hasselblad signing up to DNG but they have nothing to loose and are the two least affected.

Before you convert and bin your current version I think a little bit of caution is in order. 2 links I passed by earlier.

http://nikondigital.org/articles/library/adobe_dng.htm

http://www.openraw.org/comments/?id=226

Don

Next job is to rain on my own parade.
 

Now I have some understanding of RAW it will be important to balance the argument with a view for the users of JPEG.

I feel it is important that we do not decend into a RAW is better than JPEG without showing at which point that could become a critical issue.

As previously stated the cost of upgrading PC and possibly software can exceed the cost of budget DSLR and lens. I would rather people were out taking pics, than be in the situation of have to buy a PC upgrade first so end up limping along on the camera front. These are the people who will use JPEG and I feel a bit of reasurance that they are OK with that will be a good thing.

As JPEGS are 8 bit, a true reflection in pictorial form can be posted.

Any positive input welcome.

Don

PS Sorry in advance Stephen but this will involve a bit of pixel peeping but then its in a good cause.

Stephen,

Thanks for the link you posted. Will put it here to save people backpaging to search for it. http://www.prime-junta.net/pont/How_..._workflow.html An excellent read.

Other than prints larger than 10 x 8 which can be overcome and I will have a go later, the biggest issue seems to be shadow and highlight detail. Particularly highlight.

I have not done more than speed read the links I posted yesterday, as I visited a huge number of sites and was trying to get to the easiest to read analysis ones. It is a fairly complex subject and some stuff was really in the realms of computer boffins.

I will go away and digest this lot.

Please post any comments you have on exposing for highlights as this will apply to both RAW and JPEG but with greater implications on JPEG.

Thanks again

Don

Dull, grey, cold day ... some good reading here to keep you in the warm.

I posted the link to the RAW bit yesterday but have just made it to the index page. Lots more good info about the digital image. http://www.ronbigelow.com/articles/articles.htm

Don

This is turning into a crash course in digital. Amazing how little I knew.

Taking a bit of a break in the gallery.:)

Don

Don I have just finished reading the articles on raw on http://www.ronbigelow.com/articles/raw/raw.htm. the articles are very well written and give a better understanding on how it works. Its a good one to fall back on when needed.

I agree Christine, loads of info and easy to understand. I do not have photoshop but it is nice to know what is happening all the same. Interesting articles on composition and light as well.

Don

OK I have read the links information and accept that images in jpeg will suffer some degredation particularly in highlight and shadow areas, 8bit v 16bit.

Management has as signed off a spend on a new PC but not new imaging software.

Done with reading today as there is only so much you can take on board in one session.

Rummaged for a suitable RAW file that I could do a straight conversion on to TIFF 16bit, and JPG 8bit. We have already been down the route with D100 in camera processing of JPG's and have failed to see much missing info. So although not strictly scientific it would do for a first pass. Easy, pixel peep them at 300% and differences will be quite obvious. I was concentrating on the white areas as I was now expecting quite obvious differences in this area.

NOT SO.

It may be my screen as I have not been printing them, I do not know. Adding more than a touch of USM does visibly start to chuck out very fine detail in very light areas. More research needed. I do not have a bird image with fine feather detail that should theoreticaly show the differences easily.

I am attaching the full frame and a crop of the mill top. The crop is 289kb in order not to degrade it with compression.

Don

Don, it is generally accepted that it is better to expose for the highlights, then bring up the shadows in your image manipulation software.

The two shots below are the same image. The first is an image converted from the Raw file without any adjustment whatsoever, though ACR tells me it was 2.6 stops underexposed. The second is after processing the resulting file in CS2. The image was selectively lightened, and sharpened. I use the polygonal lasso tool and apply a large feather, anything up to 100 pixels,sometimes more, depending on the area I am trying to adjust. It was converted tomono in the channel mixer and toned using colour balance, mainly a bit red and a tad of yellow, its all personal choice.

Now make of them what you will, but the point is that they show that exposing for the highlight saved the image and the amount of information held in the file is suprising.

Stephen,

Although you say it is generally accepted, I think you may be supposing some of us know more than we do about digital. I have been treating it as I would have slide film, knew no different until yesterday/today. There is more to digital than first meets the eye. I am learning here, as I would guess are others.

Excellent example. Thank you :)

Don

Stephen,

I will for the purpose here use an anology I saw yesterday to describe my digital knowledge.

For Henri Cartier-Bresson the picture was the most important. Whereas with Ansell Adams it was to an infinite detail the whole process.

I only got my D100 because I forsaw the collapse in residual value of my Bronica kit so I did a straight swap. Photography was no longer a primary interest. That was traction engines and model engineering and last year a bit of bird watching. With the advent of this site I started taking a few pics again other than traction engine rally ones. Processing the image was not the priority as it takes time to learn all the processes.

I had never looked at a histogram as I did not understand them. Today I have read up and had a bit of a play.

That should tell you a bit about my knowledge of digital.
My sceptiscim about some things comes from reading inumerable contradictory comments on the web. Digital is not like film. That would be easy. Someone making extravigant claims could be easily and cheaply checked out.

Don

Firstly let me say that from info in the links posted and Stephens example of what can be done in RAW this is not a RAW v JPEG post.

Stephen will have to excuse me here but there is a need to understand a bit about 8 bit and 16 bit. Also as JPEG is 8 bit the effects of processing on that file.

From a lot of talk on DPR about the softness of images out of the D200 camera and why can't Nikon sort this. This suggests now that these comments are being made without any knowledge of the effects that would have after post processing on the final image. The link from yesterday reasoned that USM is fairly destructive and cannot be undone. All this shows I am not alone in my ignorance of digital.

I could not understand the result from my comparison yesterday, so today I have been a bit more analytical. ( You can crack up now if you want Stephen ). I viewed both images side by side at 1500% and used the colour picker to analyse individual pixel colour. This does show that as tones lighten the difference grows. To my satisfaction this proves 16 bit does retain more colour information.

I have attached 2 images that are screen shots. Firstly just an untouched 16 bit and 8 bit to show how crazy I am. In the second one I applied the same amount of sharpening as I usually do at the end of processing. This showed that now there is even greater differences between 8 bit and 16 bit.

With a new PC and my existing software I will be editing images in 16 bit TIFF.

With that done I am now going to look at best scenario, worst scenario for JPEG as that is 8 bit and my current machine can handle the files.

Don

While I get my head into gear to look at processing a JPEG to its best quality I would like to ask how much members generally crop an image by before printing.

Thanks

Don

While trying to understand those processing effects that are most destructive to JPEG, I returned to this series of articles. http://www.ronbigelow.com/articles/raw2/raw2.htm

Obvious first consideration is to minimise the squares from compression. I have now resorted to looking at the TIFF and JPEG at 5,000% ie each pixel is 10mm square on my screen and I cannot find the effect described here.

Why is the obvious question. Any clues ?

Don

Perhaps I should qualify the previous post. That applies to out of camera JPEGS. In other words with whatever compression JPEG Fine applies.

Don

Don refer to post 110 this illustrates the squares from compression. At high quality setting they are not evident. (top) as the quality is reduced (middle and bottom) they become very evident.

Some of the other effects shown in your link apply more to an 8 bit workflow than higher order workflows so you will see the same effects in 8 bit tiff.

I'm completely new to to RAW but my new camera allows me save in RAW and JPEG. I've been doing both so far on the theory that I may learn to use RAW as time goes on and at least the images will be available in that format. My question i; Can anyone recommend a good, straight forward article online that will introduce me to working in RAW?

Hi Dan,

Looking back to an earlier thread of yours you are using Photoshop 7. http://www.worldphotographyforum.com...read.php?t=544

I know Stephen occasionally visits here and may be able to help as he is a photoshop user. I was earlier trying to help someone, also a photoshop user but was not sure if the links I posted were up to much as I use Paint Shop.

I would guess though that you could still play around in the meantime by converting a RAW image to TIFF and then treating the Tiff image just as you would a JPEG in PS7. Your origional RAW file will still be intact and TIFF is a lossless format so it does not matter how many saves you do. Be aware though that the TIFF file will be about 3 times as large as the RAW file. On my plays with RAW that is how I do it.

The next question is can you open the RAW file to do that ?

Don