TS-E on the cheap? For architectural photography

Marcos Villaroman wrote:

brightcolours wrote:

Marcos Villaroman wrote:

I would go for the 6D and 24mm TS-E. Full frame and wide glass go very well together. You get other pluses like better high ISO performance.

That is debatable. If you set equivalent -f-ratios to get similar DOF, you need to set the ISO at an equivalent setting too. You will lose 1 1/3rd stop of "high ISO performance" right there. Then the difference is not so big anymore...

Sorry for the delay in replying. I was on vacation.

Could you explain your statement? What are you comparing that you are adjusting ISO?

One chooses an aperture to get a certain DOF. To get the same DOF on APS-S and on FF, you have to use the same aperture size. That means, a different f-value.

If you use for instance f5.6 on the 17mm APS-C combination, you have to use 5.6 x 1.6 = 8.96 = ~f9 on FF.

You can verify this: 24mm / 9 = 2.67mm aperture. 17 / 5.6 = 3mm (slight difference due to not exact equivalence)

If somehow the exposure time needs to be similar, you will have to use different ISO settings on both cameras. If you for instance will use ISO 400 on APS-C for exposure duration purposes, you will need to set 400 x 1.6 x 1.6 = ISO 1024 on FF to get a similar exposure duration.

If exposure time is no factor, the FF camera will have the upper hand more clearly, obviously.

In my post above i was too strict in my formulation. It should have said "..you might need to set....".