Thread: Slides to jpeg

And exactly how did we do that clean up iclick???? some sort of voodoo, black magic, smoke and mirrors stuff?
I need to know - pleeeezee

Originally Posted by Didge

And exactly how did we do that clean up iclick???? some sort of voodoo, black magic, smoke and mirrors stuff?
I need to know - pleeeezee

I use The Gimp (Open source image processing software available for Windows, Linux etc.) but depending on how bad it is, it is fairly labour intensive in that each slide has to be treated as required, mostly using trial and error, although some functions such as white balance can usually be applied routinely.

A further point I should mention is that there exist dedicated slide scanners that will automatically remove dust defects by imaging in infrared as well as visible light - then editing out any pixel that matches in both visible and infrared, replacing the pixel with an average of it neighbours. However, these tend to be quite expensive, I believe, and also tend to include automatic feed. Which is not much help for me as I want to transfer the label information on the slides to the image filenames.

John

Oh thanks John, must have a look asbInhave Gimp but haven't played withbit for quite a while
Cheera gerald

Originally Posted by Didge

And exactly how did we do that clean up iclick???? some sort of voodoo, black magic, smoke and mirrors stuff?
I need to know - pleeeezee

Hey Gerald. - I used photoshop. Dust and scratches filter with lots of healing brush for the fine detail.

I'm heading out he door but can send you a link later to some tutorials later..

I have a Digitech XC4881. Does slides and negs with pretty good results.
Below is a slde pic from 1977.
Mt Hopeless, looking back toward the Flinders Rangers.

Without going back to do a websearch again on the topic, I seem to recall that roughly 20 or so megapix only translates to about the old 100 ASA in terms of grain.

I did a lot of cave exploring and photography when younger, mostly on 36(?) and 64 ASA film (much finer grain than 100 ASA). Despite using high resolution scanning the sparkle that comes off the crystal formations or 'magic' fails to translate. Anyone had this issue and got a solution?

One day I intend making a light box and use a macro lens. Just got to wait for the high pixel cameras to become cheap enough to match 64 ASA film.

I miss slide film. Ideal camera would have been a digital preview before shooting in film (other than action shots). Long live the Pentax LX

Originally Posted by workingonit

Without going back to do a websearch again on the topic, I seem to recall that roughly 20 or so megapix only translates to about the old 100 ASA in terms of grain.

I did a lot of cave exploring and photography when younger, mostly on 36(?) and 64 ASA film (much finer grain than 100 ASA). Despite using high resolution scanning the sparkle that comes off the crystal formations or 'magic' fails to translate. Anyone had this issue and got a solution?

One day I intend making a light box and use a macro lens. Just got to wait for the high pixel cameras to become cheap enough to match 64 ASA film.

I miss slide film. Ideal camera would have been a digital preview before shooting in film (other than action shots). Long live the Pentax LX

I have just had a look at some sample slides from the sixties, scanned at 5Mp resolution. Blowing it up, you can see the grain in the film - and each grain is about four pixels across. This does not suggest that you need a 20Mp conversion. Obviously, not all film is created equal, and without digging out the slides involved, they were probably Ektachrome, possibly Kodachrome. The other point I note is that on most of the slides the image is blurred across several grains. (These were taken with a Practica IV). Not all films of the same speed have the same grain, and not all cameras are created equal!

The other thing to consider, and this may be where you are losing your "sparkle", is dynamic range. It is quite possible that in at least some images, the dynamic range of the image exceeds that of the scanner. This may be inherent with the hardware, or may be a function of the software. Most of the cheap scanners produce .jpg files which by definition have significant processing. Also, dynamic range will be reduced (or rather you only use part of it), if the illumination is not optimal for that particular slide and that scanner - and I do not know of any cheap scanner that adjusts illumination - they adjust the image after digitising. This is where you camera and light box may well make a big improvement, as you can change the illumination.

John

Thanks JDNSW for those thoughts, particularly the idea of dynamic range and changing illumination. My HP scanner is quite old now, but touted itself as high resolution - funny thing is when you set it to the highest resolution the software comes back with an on screen message suggesting high resolution is going to be of little value, do you want to persist!!

When blowing up the results you find the scanned image consists of frames. To me it implies the original image is divided into squares, each square separately scanned, then the collection of squares stitched together side by side to reform the entire image.

When I get around to converting the slides I will try using a daylight temperature flouro, available from the hardware, in the light box. Hopefully it will provide uniform diffusion. I have the macro lens, which I've used in the past to copy raisin sized heads from black and white school photos etc. Was good enough to give the impression that the resultant image was originally a full sized portrait.

PS I was hoping by my 'long live the Pentax LX' to drag the thread into one of those Ford/Holden Nikon/Cannon like debates that annoys everyone. Cheers.