I can take a picture directly into a 60w light bulb and the image file stays below 40k bytes, mainly because the image compensates and only the bulb is bright yellow and the surrounding area is darker, unlike the outside images which are more bright white in color.
I can’t get the light bulb to look as bright as the outside daylight pictures so it’s not a fair comparison.
The brighter the image overall the easier it is to go over 40k.
I guess we need @Vitesze to test with a Photon and see if he is seeing this same issue or not also. If he does not see this same issue then maybe I have a bad unit or it may be running different firmware.
Will also see what 4D Systems has to say.