Skip to main content
Graham-Moore
Participating Frequently
Nov 13, 2026 8:00 PM UTC
Question

64bit TIFFS

I’ve just updated Photoshop to v2027. When I stitch a panorama in Camera Raw and save it as a TIFF file it shows in Windows properties as being 64bit. I didn’t know that was possible! In the Image Menu it’s ticked as 16bit. If I select 8bit then try to save a JPEG there’s only a few options in the save list rather than the usual long list, and the nearest is Jpeg2000. Single frames saved as 16bit TIFFS can be changed to 8bit and saved as Jpegs without any problem.

What on Earth has happened? Is it thinking it’s some sort of HDR file? A couple of times when I’ve tried to change the bit depth it’s opened the tone mapping window and the image turns really bright. I’m using Windows 11.

 

Thanks everyone, Graham. 

    4 replies

    Graham-MooreAuthor
    Participating Frequently
    Nov 15, 2026 4:21 PM UTC

    Yes, it just seems odd it’s only just started. Just out of interest I went back to a pano I did before the 2027 update and tried it again in Photoshop 2026, which has remained on my system after the update. The resulting Tiff file showed an alpha channel in the channels palette. Strange!

    Anyway, thanks for your help. 🙂

    Translate
    CORCTON34033231
    Community Expert
    CORCTON34033231Community Expert
    Community Expert
    Nov 14, 2026 9:15 PM UTC

    Hi Graham — thanks for the update, and your findings actually explain it:

     

    The 64-bit figure in Windows Properties is 16 bits × 4 channels: red, green, blue, plus the alpha channel. So the file is 16-bit per channel, exactly as the Image menu says — Windows is just counting the extra channel. That alpha channel is the edge mask the panorama merge adds for the irregular edges of the stitch, and JPEG doesn't support alpha channels, which is why JPEG was missing from the Save list until you deleted it. Deleting the alpha channel is exactly the right fix — so it's not an HDR file after all.

     

    The stacking is also normal: after a merge, Camera Raw groups the merged file with the frames it came from in a stack in the filmstrip, merged file on top. Expand the stack to see the source frames.

     

    The Raw Defaults setting (Adobe Defaults vs Camera Defaults) only changes the default develop settings applied to raw files, so it wouldn't affect the merge or the alpha channel.

     

    One last tip: if the tone mapping window still appears when you change bit depth, the file has opened at 32-bit that time — check the Workflow Options link at the bottom of the Camera Raw window and set Depth to 16-bit before opening, so it comes into Photoshop at 16-bit directly.

    Translate
    CORCTON34033231
    Community Expert
    CORCTON34033231Community Expert
    Community Expert
    Nov 13, 2026 9:01 PM UTC

    Hi Graham — yes, it is thinking it’s an HDR file, and the clue is the tone mapping window: that HDR Toning dialog only appears when converting a 32-bit image down to 16- or 8-bit. So your panorama is a 32-bit HDR file — if you merged bracketed exposures, Camera Raw’s “Merge to HDR Panorama” creates a 32-bit panorama. That’s also why JPEG isn’t in the Save As list: JPEG only supports 8-bit images.

    To get your JPEG:1. First save a copy of the 32-bit file (File > Save As, TIFF) so you keep the HDR master.2. Image > Mode > 8 Bits/Channel. In the HDR Toning dialog, set Method to “Exposure and Gamma”, Exposure 0, Gamma 1.00, then OK — that gives a neutral conversion instead of the bright look.3. Now File > Save As will offer JPEG.

    Two quick checks: Windows Properties shows total bits per pixel, not the per-channel depth Photoshop uses, so don’t go by that number — Image > Mode shows the real depth. And if Image > Mode actually shows 16-bit ticked rather than 32-bit, check the Channels panel for an alpha channel — a panorama with unfilled transparent edges can carry one, and JPEG doesn’t support alpha channels, so delete it or use Layer > Flatten Image first.

    Adobe’s doc on converting HDR images to lower bit depths:https://helpx.adobe.com/photoshop/desktop/adjust-color/hdr-and-channel-manipulation/convert-an-hdr-image-to-a-lower-bit-depth.html

     

     

     

     

     

     

     

    Translate
    Graham-MooreAuthor
    Participating Frequently
    Nov 14, 2026 10:48 AM UTC

    Thanks for your quick reply. I’ve just been re-trying a couple of those pans. I’m definitely selecting ‘’Merge to Panorama’ and not ‘Merge to HDR Panorama’. After stitching in Camera Raw and opening the file in PS there’s only the background layer but the Channels Palette shows an Alpha channel, though it’s not (ticked) visible. Because it’s a background layer I can’t flatten it but if I delete the Alpha channel the file will then save as a Jpeg. I’ve never come across this before, as once I’ve saved a Tiff I’ve been able to convert to 8bit and save a Jpeg version. I’ve never had to check the Channels Palette before. Also when I go back to Camera Raw to try another stitch of the same frames they’re grouped as a stack. That’s never happened before. The frames have always been displayed separately, even when I’ve previously stitched them.

    I found in the Camera Raw prefs it had selected to use Adobe Defaults. I changed it to use Camera Defaults but it didn’t make any difference. I work from DNG files corrected from the RAW files in DxO Pure Raw, but I’ve never had any problems doing that either. I wonder if it’s something buried in the latest update.

    Translate
    Terms & ConditionsAccessibility statement
    Using the community Terms of use Privacy Cookie preferences Do not sell or share my personal information ad choicesAdChoices