The two Finnish places I'm aware of and that I believe the the ones mostly used by photo tours are Martinselkonen Wilderness Centre and Boreal Wildlife Centre. I went to Martinselkonen on an organised trip back in 2013 and had a good time (it's the source of my forum avatar). I believe at the BWC theres more wolves and wolverines.
Martinelkonen: If you're going for photography, definitely organise to go in the photography hides not the main hide. The photography hides are basically little more than garden sheds for two people – a single bed, two chairs and portable comping toilet (a glorified bucket!) – but they get you eye level. The main hide is a large thing with beds, a proper toilet, padded chairs but is in no way setup with good photography in mind. The main hide is only in the forest location, the photography hides are located in the forest, in some open swamp land and overlooking a pond, so I think you want a minimum of three nights.
Note: it's seems to be spelt both Martinselkonen and Martinselkosen. I think the s version is the original Finnish, and in English it gets anglicised to n.