dsmeltz Loc: Philadelphia

Oh! Ok. Missed that.

geolaval Loc: Laval, Quebec

Thanks for your reply Jeryh, It's appreciated.

geolaval Loc: Laval, Quebec

Thanks for the information; much appreciated.
George

geolaval Loc: Laval, Quebec

Thanks for your suggestion KK.

George

geolaval Loc: Laval, Quebec

Thanks you for replying PixHound, much appreciated.
George

geolaval Loc: Laval, Quebec

Thank for your interest RWR. Please refer to my post replying to Ron and Ricardo at the beginning of this thread. My premise is that if the digital file is grainy after scanning, a loupe hopefully will allow a better analysis for the source print than the naked eye. From there, expectations can be better managed.

RWR Loc: La Mesa, CA

I referred to your original post ... “would like to know which magnification ratio loupe would provide the equivalent 100% magnification in Photoshop.”

amfoto1 Loc: San Jose, Calif. USA

Exactly what are you scanning?

Digital images that were printed? Those would possibly have pixelization (and possibly "noise"), but not grain.

Traditional photographic prints? Those may show some grain (depending upon the ISO/ASA of the original negative or slide), but won't show any pixelization.

Black & white prints typically exhibit more grain than color prints. But it really depends a lot upon the original film type and the printing method used.

If you are scanning half-tones such as images in books, magazines and newspapers, those will exhibit dot patterns that make up those images. Magazines and books are commonly 120 to 180 dpi or higher. Newspapers are commonly under 120 dpi. Monochrome images will show the dot pattern more obviously than full process (4-color) printing where there's often some perceptual blending of the multiple inks.

Whenever you scan there is some "gain" with grain, noise or pixelization... Each new generation of an image tends to add a little (or a lot if done carelessly). They can be kept to a minimum with careful post-processing and some scanning software can automatically reduce them (ICE, Silverfast AI, etc.), but you may see some loss of fine detail if those are applied too heavily. More sophisticated NR software might be helpful too. (I use Lightroom's, Photoshop's, as well as Photoshop plug-ins Nik Dfine and Imagenomic Noiseware. The last is the most sophisticated and versatile.)

Like some others, I really don't see any purpose to a loupe. It is what it is. What really matters is the unmagnified appearance of any digital file displayed online or any print that's made from the original. Size reductions would minimize the appearance, while any enlargement will tend to amplify it.

Note: Viewing digital files "at 100% in Photoshop" is actually pretty silly. A file from a 24MP camera that's displayed on a typical monitor is like making a 40x60" print, then viewing it from 18 or 20" away... far larger and far closer than most "real world" uses. If making an 8x10 or 11x14 print from that file, it would make a lot more sense to evaluate image pixelization, sharpness, graininess, noise and even focus "at 25% or 33%". Sure, it's fine to zoom in to high magnification while doing fine retouching and corrections to images.... But it's unrealistic for a lot of the evaluations. Depending upon the resolution you scan at, you might bee seeing similarly ridiculously over-magnified images "at 100%" on your monitor... far beyond what you'll actually be using.

John_F Loc: Minneapolis, MN

When I was doing minerology the 10x loupe was recommended. I still have it.

geolaval Loc: Laval, Quebec

Actually I want to evaluate an original source photo that was scanned and presented noise or grain in the scanned file. A loupe would theoretically provide a better view than the naked eye on an original source photo. From other replies I've received, loupes are mainly used for slides and negatives. I will probably purchase one that was recommended and see the results for myself. Thanks again for your input.

geolaval Loc: Laval, Quebec

Thank you for taking the time to provide such a detailed response Alan. To provide some answers and clarification please refer to my post replying to Ron and Ricardo at the beginning of this thread. My premise is that if the digital file is grainy after scanning, a loupe hopefully will allow a better analysis for the source print than the naked eye. From there, expectations can be better managed.

I had not taken the factors in your ''note'' into consideration as I usually deal with 6 to 10 mpx digital photo files and up to 8x10 print size. This says that I am not a pro and that I am exploring an assumption to determine if it can be applied.

George

CPR Loc: Nature Coast of Florida

I'm a photographer so tend to look to photographic solutions to problems. I would put my macro lens on the camera and take a photo of the item to be scanned. Once I had a collection of macro shots of different items I would have a way to predict the output of the scanning process.

geolaval Loc: Laval, Quebec

Thanks for your input CPR. Please refer to my post replying to Ron and Ricardo at the beginning of this thread. My premise is that if the digital file is grainy after scanning, a loupe hopefully will allow a better analysis for the source print than the naked eye. From there, expectations can be better managed. Unfortunately I did not sufficiently expand in my first post.

George

RWR Loc: La Mesa, CA

I wouldn’t think you’d need more than 10X. I have a 6X Rodenstock loupe that covers an entire 24 x 36mm negative, which I use for ground-glass focusing and examining finished prints. I use a 15X Peak #2016 loupe for evaluating transparencies. I don’t know about the cheap knock-offs, but I also have an original Agfa 8X loupe that is quite sharp except for the very edges.

jackm1943 Loc: Omaha, Nebraska

Why not just scan a small area of the print at maximum resolution and take a look. That would provide much higher magnification than any loupe, I think, and would not take much time.