# Slideshow Image Quality



## wernerg (Oct 18, 2010)

In Lr3 I am running the slideshow from a collection of processed raw images. When I "Play" the slideshow the initial window says that it is preparing "previews" of all the slides. When it starts to play, the image quality is very poor, soft focus, bland. Why does it say it is preparing "previews" rather than final slides? They look like previews. If I run a slideshow with jpgs created from the same files using "Irfanview's" slideshow in full screen mode the slides look properly finished. Is there an image quality setting somewhere in the Slideshow module to prepare full quality versions for the slideshow or do I have to use the jpgs in the slideshow. I really don't want to include exported jpgs in the Lr3 catalog just to do slideshows. 

Werner


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## Mark Sirota (Oct 18, 2010)

Welcome to Lightroom Forums.

Try this -- before running your slideshow, go into Grid, select all, and Render Standard Previews from the Library/Previews menu. (If your standard preview size is smaller than your monitor, adjust that first or render 1:1 previews instead.)

Alternately, check the "Prepare Previews in Advance" checkbox at the bottom of Slideshow's right panel before starting your slideshow.


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## wernerg (Oct 18, 2010)

I had both settings already but I reset the standard settings in the Library again just to be sure. I get the same soft, unsharpened image again. I then imported a jpg that was exported from one of the raw files, put the jpg into a slideshow and again it looked soft yet when I look at the same jpg in a full screen image viewer it is crisp and sharp. Could there be an overlay in the slideshow that is softening the image? I'm using the caption and rating preset. 

Thanks
Werner


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## Mark Sirota (Oct 18, 2010)

The only other thing I can think of is that Lightroom's Slideshow module doesn't include the export sharpening that your exported files probably have. Could that be the difference? I wouldn't have expected that to be enough to be described as "very poor, soft focus, bland"... But maybe.

Did you try rendering 1:1 previews first, just to be sure?


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## wernerg (Oct 18, 2010)

Sorry, I mis-read your earlier instructions. I had standard previews.  I rendered 1:1 previews and they now look considerably sharper and crisper. It also didn't help that my standard preview was too small. Do the standard and 1:1 previews both include the changes made in the Develop Module?


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## Mark Sirota (Oct 18, 2010)

Mostly. 1:1 previews in LR3 include everything in Develop, and are compressed JPEGs in the Adobe RGB color space. The JPEG compression level is determined by the preview quality setting in Catalog Settings.

Standard previews may not include sharpening and/or noise reduction, depending on preview size relative to original file size and camera/ISO settings. They too are JPEGs in Adobe RGB.

When a preview is rendered, the smaller previews are downsized from the largest preview rendered. So if you render 1:1, then all previews include everything (though sharpening can be masked by downsizing).

Previews are used on the screen in all modules except Develop. In Print, they are also used for draft-mode printing. When you export (whether it's Export, Publish, Web, a non-draft Print, or an exported slideshow) files are re-rendered with everything.

P.S. You should set your standard preview size to at least as wide as your widest monitor.


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## wernerg (Oct 18, 2010)

Thank you very much for your help. My Standard Preview is now set correctly. The slideshow, perhaps because it runs full screen was the first time I noticed that the images didn't seem to be as crisp as the "finished" IQ that I see in the Develop Module or the jpg outputs. The jpgs I was using to compare were rendered at full sensor size, the original standard previews were undersized for the monitor. 

Thanks again,
Werner


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## boneywhitefoot (Oct 21, 2010)

make sure you dont have a border around your photos ,it really sucks watching your photos looking like they do in lightroom removing any border options inproves the images but still they arnt the best.


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## Mark Sirota (Oct 21, 2010)

Werner,

I'm trying to prove that this is a bug in Lightroom, and so I'm trying to recreate your problem, but I can't.

Can you tell me, when you saw this problem, what size monitor were you using (e.g. 168'x1'5'), and what size were your standard previews set to?


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## boneywhitefoot (Oct 21, 2010)

Ive posted about this before and I use a 3'inch dell .its very plain to see and disapointing when showing clients your work,I try to sit them further away from the screen.


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## Mark Sirota (Oct 21, 2010)

Can you give me a specific recipe to follow so I can try to recreate this?


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## boneywhitefoot (Oct 21, 2010)

Dell WFPHC 256'x16''
geforce 88''gt

never noticed it with LR1,wasnt till LR2.3ish.

its kind of like some sort of compression problem
ive tried making images exactly the same size as the screen to no effect,how ever smaller than srceen size is sharp and on the nail.


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## Morten Beier (Oct 23, 2010)

Hi Mark
I have the same problem as Werner has already described. I have been through all your suggested steps, but I still have a problem.

Pictures from on-land tends to look fine, but most of my shots are under-water. Things like the grading of blue water-colours tend to have a low quality .jpg appearance. I can only make it look good by exporting to .pdf slideshow (which changes the deep blue colour a bit towards a greener look) or viewing directly from the develop module, which is quite annoying - I really like the possibilities in the slideshow module.

Can something be done to improve the image quality?

BR Morten


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## Mark Sirota (Oct 23, 2010)

Could it be that you're seeing JPEG compression artifacts?

Any chance you can export a small catalog with negatives and previews, zip it up, and send it to me via yousendit.com or dropbox or put it up on a web server where I can download it?


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## Braders (Oct 23, 2010)

[quote author=Mark Sirota link=topic=11345.msg7621'#msg7621' date=1287427864]


Did you try rendering 1:1 previews first, just to be sure?
[/quote]

This is the "must do" prior to slideshow. Has been since 1.'


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## wernerg (Oct 23, 2010)

Sorry that I fell behind on this discussion but originally I had the preview set to 1'24 and medium quality on a 125' x 1'24 monitor. It wouldn't seem that this would be so low to be noticable but it was. I look at 1'24 jpgs all the time and they look fine. I "fixed" the slideshow by going to 1:1 as you suggested. I also raised the "standard" preview to 168' and high quality. I now have a new 192' x 12'' monitor and so far these larger standard previews seem ok but I haven't tried them in the slideshow. I did try a quick test by making 1:1 previews and looking at them in the slideshow and they look fine. I wouldn't have a problem showing those in public. 

Originally, it almost seemed as though the slideshow was using an unprocessed, unsharpened earlier version of the images. I didn't realize that it was just too small. Also, the quick dialog that shows up at the start of the slideshow says that it is preparing "previews" so thought that there must be another step to get to "final". I guess there is and it is making the 1:1 previews.

Werner


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## Morten Beier (Oct 24, 2010)

Hi Guru Mark 
I have now put a catalog, which clearly shows the problem at:
http://arcticdive.dk/ftpserver/

It contains only one image, but I guess thats enough.

Speaking about the Slideshow I can't figure out how to put the slides in the wanted order? I'm using LR 2.7


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## b_gossweiler (Oct 24, 2010)

[quote author=Morten Beier link=topic=11345.msg76552#msg76552 date=1287958611]
... Speaking about the Slideshow I can't figure out how to put the slides in the wanted order? I'm using LR 2.7
[/quote]

You have to run the slideshow based on a collection. Within this collection, you can put the photos in a user sort order by dragging/dropping them in Grid view (drag them from the center of the thumbnail). Then use the collection as a base for the slide show.

Beat


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## Mark Sirota (Oct 25, 2010)

Thanks for the catalog. To make this easier, could you zip it up so that I only have to download one file, instead of an entire folder structure?


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## Morten Beier (Oct 25, 2010)

@ Mark .zip file uploaded 

@ Beat Thanks !!!


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## Mark Sirota (Oct 25, 2010)

Okay, I've got your catalog. I see that it's an LR2 catalog with standard previews set to 144' pixels.

I haven't yet tried it in LR2, but in LR3.2 it appears to work fine on my setup. Can you tell me exactly what steps you follow from here to illustrate the problem? I tried opening the catalog, then pressing Control-Enter to start an Impromptu Slideshow.

Later today I'll try it in LR2, if someone else doesn't beat me to it.


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## Mark Sirota (Oct 25, 2010)

In LR 2.6.1 I don't see the problem either. The first time I invoke the Impromptu Slideshow, I very briefly see the too-small preview, but it's gone almost instantaneously and looks perfect thereafter. If I start fresh and then go straight to the Slideshow module, it looks just fine in the preview there.

I still need a specific set of steps to follow to reproduce this.


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## Morten Beier (Oct 25, 2010)

Hi Mark
All I do is to chose the image in library or develop and then go to slideshow. The only place I get a good image is in develop. The colorgrade in the blue water has very clear pixels when watched in the library and slideshow - impromptu or not.

Try to switch between develop and any of the other modules with only this picture selected. I hope you can see the difference..?

BR Morten


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## Mark Sirota (Oct 26, 2010)

I don't see anything. Could you post a screen shot?

Could it be that you're seeing JPEG compression? The gradient of the blue in the water could get posterized... I can see a little posterization, but it's not objectionable. I don't see anything I'd call "clear pixels".

Another remote possibility -- perhaps your monitor profile is corrupt. If you calibrate your monitor, try re-calibrating. If not, there are some other diagnostics we can try, let us know.


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## boneywhitefoot (Oct 26, 2010)

in that case would it look the same in develope mode as well ???


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## wernerg (Oct 18, 2010)

In Lr3 I am running the slideshow from a collection of processed raw images. When I "Play" the slideshow the initial window says that it is preparing "previews" of all the slides. When it starts to play, the image quality is very poor, soft focus, bland. Why does it say it is preparing "previews" rather than final slides? They look like previews. If I run a slideshow with jpgs created from the same files using "Irfanview's" slideshow in full screen mode the slides look properly finished. Is there an image quality setting somewhere in the Slideshow module to prepare full quality versions for the slideshow or do I have to use the jpgs in the slideshow. I really don't want to include exported jpgs in the Lr3 catalog just to do slideshows. 

Werner


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## Morten Beier (Oct 26, 2010)

Hi again

yes, I do calibrate my display, and just tried to do that again. It didn't change anything. And yes then it would have affected the develop view too 

I have added 2 screendumps to http://arcticdive.dk/ftpserver/ - despite the small size it should be posible to see the difference here.

All the best


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## Mark Sirota (Oct 26, 2010)

What I see there is JPEG compression artifacts, which show up as purplish bands in the blue water. is that what you're looking at? The Slideshow one still looks just as sharp to me as the Develop. Setting your Preview quality to High may reduce the effect somewhat.

In Library and Slideshow, you're viewing Previews, which are compressed JPEGs. In Develop, you're viewing a direct rendering of the raw data, without the compression for storage and rapid display.

Your screenshot looks worse than either of my monitors, though not significantly worse.


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## Morten Beier (Oct 26, 2010)

Yes, that's what I'm talking about. and some of that purple turns into squares. All in all very .jpg'ish.

I guess there is no way around it - except if future Lightroom versions would allow slideshows based on higher quality .jpg previews or .pdf. 

I think it is a shame, since it makes the slideshow function not very attractive for wideangle underwater photography. Maybe a niche, but still interesting for a few 

Well, thanks a lot for your help this far. Should I send the suggestion to the forum for that?

BR Morten


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## boneywhitefoot (Oct 26, 2010)

with my problem Mark its just a lack of detail and sharpness, in general


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## Mark Sirota (Oct 26, 2010)

Okay, I think we've gotten to the bottom of Morten's problem. It can be reduced by setting Preview quality to High, but at the moment, that's the best you can do. You could certainly file a feature request for previews that don't show such offensive artifacts; include your file and screen shots.

If boneywhitefoot's problem is different, let's track that one down. How about a sample catalog and/or screen shots, as Morten provided?


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## boneywhitefoot (Oct 26, 2010)

cheers Mark,if it means setting up a send it account and stuff it may take a few days, im under a wee bit of pressure here trying to get a new website up and going.
Im pop back when i have a bit of spare time.again thanks so far.


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## Mark Sirota (Nov 19, 2010)

boneywhitefoot: Are you still able to reproduce the "lack of detail and sharpness" in Slideshow? I'm still interested in trying to track that one down, if you've got the time.


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## boneywhitefoot (Nov 19, 2010)

hi sorry Ive been up to my ears in work Ill get it to you in the next few days,sorry about that.


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## boneywhitefoot (Dec 8, 2010)

any luck replicating my problem????


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## Mark Sirota (Dec 8, 2010)

I haven't had any luck, but I confess, I seem to have lost track -- did you send me something to try?


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## boneywhitefoot (Dec 9, 2010)

yep Ill send them again.cheers.


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