Question about JPEG losses.

[FundyBrian]

Everyone knows jpeg compression is undesirable, which is why some apps give us the option to save images as uncompressed tiffs. On the computer you would always work in tiff format to avoid compounding jpeg losses, like making a photocopy of a photocopy. If this is new to you, it is important.

I'm concerned about the app-to-app chain within the iPhone, iPad, or iPod. Few apps support and save tiffs. So we take all the care to save the original image as a tiff, then open it in another app, edit and save, this time jpeg is the only option. Jpeg compression losses. Now we move on to another app, more editing and resave as jpeg. More losses. Now we add a frame in another app, and save to jpeg. More losses. Now we go and add a photo credit line in another app. More jpeg compression losses. This is getting serious. It's a good thing that grunge effects are so popular.

It looks to me like the most desirable thing is to shoot an image, save it as a tiff and continue to do all the editing in one app before the final save, preferably to tiff.

Does anybody else worry about this?

I have noticed that some apps can pass an image along for further processing to certain other apps within the phone. In this case, is the image being saved and reopened or is it actually continuing work on an open image without jpeg compression losses in between?

 

[Kevin Barrett]

I have thought this over and am personally cognizant as I App away. I realize that generational copies of copies can lead to less than desirable outcomes but sometimes happy surprises.

There is no (artifact) FREE lunch. With that said, it would appear that some apps do better than others with regard to maintaining JPEG quality. This of course could be a hopeful illusion on my part, but I have been happily impressed with some of the heavily app'd JPEGs I have worked and re-worked.

Ultimately, I agree that doing as much as you can within a single app, probably will yield superior pixel level results. Some work is conducive to that level of care, while with other desired outcomes it may practically matter little if the original was a TIFF or JPEG.

 

[Lzed]

I would like to see other editing apps use tiff to minimize the compounding loses. It may change as more people with dslr's want to edit on an iPad but a lot will depend on Apple taking note of what people want.

I am not sure about what it does when you open in another app. Might have to play around and see...

 

[Chris / interealtime]

Staying in one app (or using only apps that support TIFF) will minimise it, but honestly this isn't really worth worrying about unless you're obsessing about image quality on a very fine level. It's hard to see any degradation at all under normal circumstances, even at 100% zoom and several saves.

Personally (after having experimented a bit with this), I think the extra speed and disk space you get with JPEG far outweigh any additional quality from TIFF.

 

[RoseCat]

ProCreate allows you to safe as a .jpeg or a .tiff. Perhaps the solution (for those with iPads) is to create your image, then open it up in ProCreate and then save it as a .tiff as your final step.

 

[dcmacnut]

I've done some preliminary expirimenting saving and resaving a JPEG repeatedly in Photo Toaster, with no "apping" done in the process. Realistically, it takes aboug 10 or more saves before I start noticing artificats, much of which could be chalked up to noise from the original photos. I would argue that in the apping process, adding a filter, a texture, a frame changes the original, that the artifacts become less an issue. I prefer apps like Filterstorm that let me to as much as I can before exporting. I especially like apps with the "send to" or PhotoAppLink function to transfer images between apps. This allows you to to avoid those intermediate saves between apps and associated compression.

 

[FundyBrian]

Yes, I like that "open in another app" feature, as well as being able to copy and paste to another app. I'm sure this situation will get better as time goes on. It is hard to see the losses on the iPhone screen. However, some pictures that look good on the small screen show poor image quality when viewed larger on my Apple Cinema Display.

 

[Chris / interealtime]

Yes, I like that "open in another app" feature, as well as being able to copy and paste to another app. I'm sure this situation will get better as time goes on. It is hard to see the losses on the iPhone screen. However, some pictures that look good on the small screen show poor image quality when viewed larger on my Apple Cinema Display.

It's unlikely that it's related to JPEG compression - do you see JPEG artefacts (small blocks of colour, 'rings' around small details)?

One issue is that sometimes it's hard to tell whether a photo came out clear or blurred on the iphone screen. Another is that some apps lie about their resolution - worst case, it'll save 8 megapixels but only actually process at 0.5, meaning you get a horrible blurry mess when you view it on a bigger screen. You can spot this easily, the photo will be blurry, and any diagonal lines will show a staircase effect instead of a smooth line.

 

[Kevin Barrett]

Very interesting!

 

[J3Bishop]

I hate the loss of resolution sometimes is good like in some vintage grunge style photos but for something more detailed the photos are really bad when you print , for "fix" this i use perfect photo suite PC before print.

 

[dcmacnut]

I It may change as more people with dslr's want to edit on an iPad but a lot will depend on Apple taking note of what people want.

I started editing DSLR photos exclusively on my iPad 1 in 2010. Long before I had an iPhone. Filterstorm was the top of the line editing app of its day and could handle large RAW files. (Editing RAW images on the iPad is a topic for another day.) Others apps have come and improved since then, but Filterstorm is still my favorite.