If you are looking for a 35mm equivalent and want to buy one of the current EF lenses, then the TS-E 24 II is a far better choice than the TS-E 17 for the following reasons.
- You lose a lot more quality with a 2x converter than a 1.4x
- The 24 is sharper than the 17 to start out with
- The 17 has serious flare issues (no surprise given the front of the lens). The 24 handles flare very well.
- The 24 can take filters, the 17 cannot (or at least cannot easily...)
- The do not have to worry as much about the front of the lens and don't have the huge lens cap to carry around
Those are all important considerations.
My concern, vis-a-vis "17mm vs 24mm", is that I will lose the wide end of the focal range (between 17mm and 24mm). It seems like a lot of the potential work I might see for this lens is with interiors. And it would seem like 24mm is going to be too tight for kitchens, entryways, master bathrooms, etc.
The 35mm equivalent is really just a "bonus" mostly, not as crucial as I might have suggested with my comment. My biggest concern is not being covered on the wide end. I can always crop a 17mm shot down to 24mm, and so on.
If I were shooting primarily outdoor shots with plenty of distance, then the 24mm would be my choice. But for the price tag, the versatility of the 17mm seems more practical for me. Maybe if there was a reverse teleconverter... then the 24mm would look a lot more practical. ;-)
I do quite a bit of RE photography and IMHO you really need both of them. There will be times you have to deal with flare and the 17 isn't an option. There will be interiors where the 24 is not wide enough. You will have to shoot in the rain (at least I do here in Seattle
and the 17 is most definitely not the lens you want for that.
I use both lenses very heavily. In general I use the 17 for interiors and the 24 for exteriors, but not always. I find that in very large homes the 24 is more appropriate because you're not trying to make the home larger at that point - you're trying to sell its features.
Here is an example of what I meanSunrise Melody
, on Flickr
While here is a shot where the 17 was more appropriateMaster Bedroom
, on Flickr
I also use the TS-E 90 occasionally - mainly for shots of the property from the dock if it is a waterfront home. I have at times wished I had a 45 but it is relatively rare. The Canon 45 is not a great lens though and if I had the money I would pick up the Schneider 50 instead.
I think for your standard run of the mill house you can get away with a 17-40 - a TS is overkill, but when you shoot properties that are advertised nationally and make magazine covers, then you need to invest in the proper equipment.
Note that for what it's worth, when I travel I rarely use my 17 (the Burj Khalifa was a 2715 foot exception). My 24, on the other hand, is my most used lens after my 70-200 II.