I have been trying to complete on Photogrammetry projects but keep getting stuck

I am an experienced photographer (old school, with films and chemicals) and am really keen to produce images using Meshroom and Blender, however the mysteries of the process are very challenging.
I cannot find how to reduce the file down to a reasonable size. I decimated the mesh in blender to a factor of 0.0001 and still have a file over 300mb.
I am grateful for any advice you can offer.
Tony.

Hmm… Just a wild guess here: how big is your texture size? Have you tried to optimize or rescale them?

Hello Warkarma,
thanks for your suggestion. I have not tried to alter anything from the meshroom image other than to trim it of the main subject. I assumed that the decimate process in Blender would reduce the texture and material proportionately.
I will look into it, also, maybe how to get less density from the meshroom image.
Thank you.

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Hi @oldnslo, have you tried simplifying the mesh in Meshroom itself before export as shown in this tutorial?

Can you share a link your model? or a some screenshots of the files?

Hello Nebulousflynn,
I tried yesterday, I reduced by far to much and did not get a full reproduction of the image. I went back to it today after looking in the mesh node at how many points it used I reduced them down to a third of the original. After cutting away all the surplus background I have a smaller image to work with.
Thanks for your help.
oldnslo.

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hi @oldnslo
You should look at your output file structure ; in OBJ format, the mesh (OBJ) and the textures (JPG) are in separate files, so that you can estimate the relative sizes. If the jpeg texture files are significantly large, you can very easily reduce this : in photoshop (or equivalent), just downsamble the jpeg files ; it will hardly reduce quality, but drasticly file size for example 4096x4096 -> 2048x2048. you probably won’t gain a factor of 4 as you might think, but easily more than 2. You can also lower jpeg quality quite a bit before it really shows. Still in photoshop, saving with 5-6 quality (instead of 12), makes a huge difference in size, but hardly in viewing quality.
This has to be done in parallel with reducing poly count, which usually does not modify the textures.

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Thank you for your suggestions. I have DL Gimp and will try to reduce JPG files. Who said photogrammetry was easy? I will ‘get it’ eventually and then start producing some interesting images.
I am grateful for all your tips.

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