Hi, assuming you are focus stacking, you could try using macro tubes as a very inexpensive experiment, just make sure that either the tubes have the electronics to let you stop down the lens or you can stop down manually on the lens, otherwise you will be shooting wide open and you will have a tiny depth of field and need to stack a lot of images. I cannot guarantee the results of this but it may well be worth a try. For instance I used my super cheap tube set to take this image of a log at f22, using an old manual lens i picked up in a car boot sale for £4 . adapter cost me around £12, tubes cost me about £10-15 (with electronics they are a lot more). So total cost of under £30, and obviously you can use the tubes on any lens: This is shot at 80mm from abut 30 cm away, so in theory would give a very precise mesh although there would be a lot of work needed: