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Hi All,

Just recently found that I'm doing something wrong during my JPEG conversion from TIFF. Usually, I'm shooting RAW, then working on TIFF and printing to Canon i965 but this time I want to print a huge amount of photos and it will cost me a fortune to buy all paper and inks. So, I decided to use one of online printing labs but my JPEGs don't look like TIFFs

Could you tell me, in your opinion, what is the best procedure to convert TIFFs to JPEGs with PS?

Just one dumb question

Why do you need to convert from TIFF to Jpeg for printing?

Another dumb question?
Why are you using TIFF for editing?

I keep it in PSD format as long as poss and then convert to high quality JPG or TIFF for printing... Most decent labs / kiosks accept TIFF...

Mudder,

Hmm. I mentioned ONLINE lab. It means I have to upload files there. Say, 200 tiffs, 30Mb each ...... Do you think it's a good idea?

John,
I'm using tiff historicaly because PSD wasn't understood by 3rd party software before. Meanwhile there is almost no difference between them, so, I can use PSD or TIFF but anyway I have to convert them to JPEG by reason mentioned above

oh I'll crawl back in my hole now...

Hey! Hold on! Before crawling back to your hole you have to tell me how to properly convert TIFFs to JPEGS!

I tried to use TIFF at an AGFALab Kiosk (Teds) and they fell over with my TIFFs no matter what options I used for the TIFFs.

Sorry can't help HLOP.

G'day, Just popping my head out for a tick

No sure what you mean by your JPEGs don't look like TIFFs. Are you losing colour saturation, detail etc? I assume you're converting in a batch mode with the same settings for all images, I assume there's no change in res during the conversion, etc? Out of curiosity what are you using for the TIFF->JPEG conversion?

Kipper, when you trouble with your TIFFs, did they contain alpha channel info (like saved selections etc)?

I've always just used a single layer TIFF (with no alpha channel stuff) for printing, but can understand that if you are ftp'ing the files to the printing service, ya don't wanna ftp huge amounts of data hence the conversion etc...

mudder wrote:Out of curiosity what are you using for the TIFF->JPEG conversion?

I was following directions from one of russian photo web-sites. Algorythm is:
1. Gaussian blur 0.8
2. Re-size
3. Unsharp mask
4. Convert mode to 8 bit
5. Save as JPEG. Quality about 10-11 for printing, 8-9 for web

Can't really tell what's different but it is different. For example, colors are still same but a bit different tone

What's with the Gaussian blur of 0.8?

I just leave it as is, full size jpeg at max quality.

Also are you doing save for web or save a copy? Not sure whether there's a difference but I remember somebody mentioning that there is a difference...not that i've seen it before.

If you're uploading 30 full sized jpegs, I suggest setting it up to go and leave it overnight while you sleep

I don't remember why have to do gaussian blur - there was an explanation but I red it long time ago.

Also, I'm not sure If there is a reason to leave it full size, because I'm going to print 10x15cm.

So, my target is minimization of file size without noticeable loss of quality for printing 10x15 pictures.

Ahh alright Sorry I thought you were going for larger sized prints.

Maybe reduce it by 75% then but keep the quality at it's maximum. Not sure which lab you are using, but the lab I use re-compress the jpegs for me using their program. What setting that is, I'm not sure but from the prints I've made I can't see any loss of detail.

My reason for leaving it at full quality (0 compression) is if you give them something which has been compressed (ie. jpeg crapness), there's a chance you'll get exactly that in the final print. Mind you, this is my personal theory and I dont' really want to risk testing it out (erm...call it the perfectionist syndrome)

Somebody else may have compressed it to 80% and the images might have printed out fine.

G'day,
Not sure why the gaussian blur or the re-size? What are you re-sizing down to? Are you re-sampling the image when re-sizing? Only reason I ask about the re-size is I just assumed you'd want the highest res possible when printing and just use the DPI to set the image size maybe?

I've always just used max res (including jpegs) for any printing, but I'm certainly not knowledgeable on printing though as I've only printed a few, mainly large size though (16"x20" and up)...

The gaussian blur sounds very strange.......

cheers
bp

big pix wrote:The gaussian blur sounds very strange.......

It sounded strange for me as well. Just searched through that forum and found many people suggesting gaussin blur before downsampling of image. Most of the were with no explanation. Found just one and I'll try to tranlate it:
Use gaussian blur with radius 0.3-0.7, if you won't use it, high frquencies in image will be converted to useless noise and "hard" dots

Maybe PS gurus like Sirhc55 can explain it in more apprpriate terms and words

I must admit that when I print I am using a PSD or sometimes a TIFF file and I do my own prints, sizes vary from 100mm x 150mm to 61cm x 100cm and wider
I use the same file for large prints and small prints with no loss of color when I print the same image big and small

cheers
bp

I've never heard of that gaussian blur technique either - certainly an unusual approach. Perhaps it's an attempt at minimising the averaging effect of jpeg in large expanses of high detail by averaging/blurring it to a lesser degree
Just my wild speculation on the rationale.

Interesting.

I have just had some 6x4's and 8x12's printed and I sent these across the net to the store. I was originally going to send the TIFF's but with 100 6x4's, you can imagine the size (it was about 550Mb - from memory).

For the 6x4's I:
- resized a copy of the original (cropped if required) to 1800x1200@300DPI = 6" x 4"
- saved as TIFF for archiving
- converted TIFF to JPEG using PSCS2 Image Processor (quality set to MAX, 12)

This bought the total size down to about 170Mb, which was much more manageable to upload via the net.

Interestingly enough, whilst uploading, I noticed that as the files were being sent, they were also being compressed first (presumably by the application that is used to send the files - this was for Camera House).

I have the photos now and they came out very nice indeed. In future, I'll use HQ JPEG again without a 2nd thought.

Has anyone ever had any problems printing from JPEGS in this fashion ??