Yes, I'm sure the Lee Frost has been able to get these good results that way - what would be interesting to know is, did he use the multiple processings simply to extend the DR of the photo he had to normal limits, or did he take it beyond this (ie into clipped shadows and highlights).

If the former (the shot was within the cameras DR anyway), could he not have more simply stuck with the single original image and extended its DR in the usual manner (levels or curves) and then been able to get more or less the same good results from his HDR processing?

If the latter (the image was blown from the start) then what would be the point in pulling down the clipped highlights or pulling up the clipped shadows? There's no detail there to contribute anything of quality to the HDR output.

Looks like I'm with Smeggy on this one.

Just for clarity, my post above does support the points made by Smeggy in relation to multiple processings of a single shot for further HDR work.

The author of my book does say that you can use a single image file (with a good DR) and get good HDR effects from it. You probably don't need specialised HDR software for this now - the Topaz 'Adjust' plugin provides this sort of option, and I've just seen that a new release of my favourite RAW converter, Sagelight 4, now includes an 'HDR' module, but only for working on a single file. The Sagelight creator says that 'HDR' has become so synonomous with the highly stylised overblown look, that is now what people think of when thinking 'HDR'

But real HDR is not this at all - it is simply the merging through the 'tone compression' technique of differing exposures of the same scene.

I've just finished reading a book called 'Practical HDR' by David Nightingale - recommended, good examples, nice explanations of practical purposes behind differing HDR techniques (just as we're discussing here) and an overview of using the main software products.

He talks about single image HDR towards the end; he regards it as mainly a means to 'unify the tonal range of an image' (ie reduce it !)or to allow creative HDR effects and increased detail in an image when it had not been possible to shoot a number of bracketed exposures.

He specifically says '...you only have a single exposure to work with, so you ideally need to make sure that the dynamic range of the scene is lower than your cameras range from the outset - any shadow or highlight clipping at the exposure stage will be carried through to the final image.'

The implication from this is that if the DR is already full across the histogram, then just producing additional underexposed & overexposed copies for HDR processing is of no benefit. The point of the bracketed exposures is that each one is optimised for a certain tonal range, allowing the HDR software to use the best bits of them all. The different exposures from a single shot situation will just compromise the quality in some of the tonal areas.

I find a good technique when using my old Pentax MF lenses (which have a firm smooth movement to the focus ring) is to 'focus through' the subject first, sort of going just slightly past, then backing off again to out of focus, and finally coming through again to achieve the perfect focus.

Its sort of three movements, but I find that having moved the ring past the focus point firstly, coming back again and then trying again kind of teaches your fingers the exact amount to move. I found with only one attempt you're never quite sure if you've nailed it exactly.

I don't think these questions are important unless you are outputting to your own printer - then yes, you have to worry about filling up your sheets of paper. For online printing, the company will have their range of standard sizes which you choose for each photo. Firstly you go for the one that most closely matches your desired size and the aspect ratio of your shot.

Once the photo is uploaded and you've selected the print size you should see a thumbnail of your photo with a border around - this represents any small differences between the dimensions of your image and the sheet of paper. So long as your images have not been resized (in Photoshop for example) to an unconventional width/height/length, then the border should closely match your image.

Bear in mind that our cameras produce a photo of a standard dimension (and resolution). Because I don't print my own photos I don't even think about this - I don't need to know.

When the images are opened in an editing program they retain the dimensions and resolution that the camera output unless you change it. You will have conventional sized photos which should fit into most standard print companies choice of print sizes.

If you choose a print size that is slightly different , then you'll see from the border markings whether it's going outside the edges or it's within the border. You usually get a choice (a drop down arrow) to decide whether to have the photo cropped to fit the border, or to be resized to fill the sheet of paper.

I know this does remove the final ultimate control over the exact edges of your shot, but it makes it very simple! Its probably best to allow a little extra space on the important edges when cropping in an editor in case you lose a bit when its printed.

No, I can't view these photo sites, as they're classed as social networks (time wasters at work!) Not at all like PentaxUser! Hopefully I'll have some home time soon to try it out. Thanks for the advice.

I don't believe it is possible to scan a slide or neg without there being some unavoidable image 'manipulation'. To scan you need scanner software I believe, and this will always have some default settings that are applied even if you don't touch anything - eg. sharpness, contrast, brightness - all things that are usually applied to digital images also as a matter of course.

A scanner is, sort of, taking another 'shot' of the original - it has to apply some basic settings to output the scan. So I don't think there can be such a thing as a 'pure' unedited scan. In most cases the scans can be 'improved' (bad term?) by altering the settings on the scan software, or they risk looking dull and unsaturated once seen on the computer.

I'm assuming the reason that original slides or prints can't be sent in is because of the extra effort in handling them or viewing them?

Yes, K, I should have clarified that. When I ordered some mega sized prints recently on FOTO.com as I was choosing the print size I was seeing a comment on quality for each photo - eg. 'optimum', 'acceptable', 'reasonable'. As I wanted these big prints to be on the wall I made sure I ordered the maximum size I could get that maintained the 'optimum' rating.

The results speak for themselves as even the biggest 60cm by 90cm prints show no reduction in quality from the same shots printed at 12" by 8".

But what is significant is the very obvious difference between those photos shot with my K7 (14.5mp) and others on a digital compact (9mp). The maximum size at 'optimum' from the compact was 30cm by 40cm (still very impressive). I'm guessing that so long as the file is at least a few megapixels then theres enough data to produce quite good enlargements.

I'm not seeing any links at all. In the example of wokingrob I mentioned, I just see his text, there is nothing else in his original post at all, just the complete grey rectangle around his text.

I've used numerous online printers (check out my post for the latest)link, and never had any issue with image size or resolution.

It seems that so long as there is enough data in the file for the size you are choosing to print, then the website software does all the dirty work and automatically creates the right output figures. Thats been my experience anyway. I have always used my maximum quality JPEGs to upload using the highest upload quality option (slowest). These files are usually around 5-10mb. This is exactly what I used for the FOTO.com poster prints I raved about in that earlier post, and there is no discernable loss in quality at all.

I don't think it will make any difference what resolution your files are - they will just be automatically adjusted to whatever the printing system requires for each particular print size.