Canon R5 + RF 28-70mm Tips + Tubes

Sittatunga wrote:

Ephemeris wrote:

Hi folks

Any tips or help for the use of this lens appreciated. It will replace an older EF 100 F2.8 lens and also an RF 28-105 F4 lens (I don't really like this lens - the EF was doing as much work for us).

The lack of IS is making me a little nervous and also that I can't use a TC.

Do any of you use this lens with extension tubes/rings? Is the AF still usable?

What size objects are you trying to photograph in the field?

It depends. It can be the pintle of an injector, a foreign object within a conformal coat or an entire active suspension corner.

I did pass you a link regarding TCs in the 100mm EF. We certainly use a TC with it (I have said this already).

So from tubes to TCs and just natural.

Your current macro lens will AF down to a field of view of just over 36x24mm without tubes, while the RF macro will go to just over 22x15mm without tubes. Neither will work with a Canon Extender (TC) without an extension tube between lens and TC, because the TCs penetrate further into the lens mount than the rear elements are recessed.

I've coved the TC above and previously passed a DPReview link on the topic.

The RF macro has the advantage that its IS is designed to work in conjunction with your camera's IBIS; the EF 100mm L macro's wasn't, because IBIS wasn't a consideration for Canon when it was introduced in 2009.

The RF macro won't allow a TC which is a mallace.

The 1.5x magnification is certainly a bonus, a big one for us.

The likely improved AF speed a bonus.

The likely improved image stability via the IS and IBIS a bonus.

However. The EF100 would be sold, the RF 24-105 sold (we are not a fan at all of this lens) to provide some funds.

First, a 28-70mm standard zoom is definitely not a replacement for a macro lens.

I'm not trying to replace it but some of its function will be covered by the new lens.

You can't use it with an RF mount teleconverter,

Agreed but I covered this.

because Canon's teleconverters penetrate something like 17mm inside the lens' mount and the rear element is only recessed about 4mm.

It would work if you mounted it on a 16mm extension tube, but then the maximum focusable distance would range from less than 300mm from the front of the lens at 70mm to somewhere within the filter threads at the wide end.

I hadn't considered adding a tube but we don't have an RF TC so that may be why I hadn't given it a thought. Helpful information tbought. Nice to have some fresh thoughts.

The lens would work with extension tubes, but a standard zoom lens is a bit of a nightmare with extension tubes and almost impossible to calculate tube length and focus in the field because of its length.

Do I need to calculate it? Let's say a 16mm tube is added then I can assess if it's helpful or not.

The question is how it may affect the AF.

Even if somebody were to produce an RF mount TC without protruding front elements, a 1.4x would turn it into a 40-100mm f/2.8 with probably noticeably worse performance than the RF 24-105mm f/4 and certainly more than twice the weight.

Sometimes slightly better, slightly worse isn't the throught process it's about can it, will it to allow me the opportunity.

The opportunity is king here.

Weight - well EF-100 400, TC, R5 and grip, flask, laptop etc. Just have to bite my lip and moan.

A 2x TC would give you a heavy (1kg heavier than the RF 70-200mm f/4) 56-140mm f/4.

Having the close to 100mm field of view would be the need for the 1.4x TC. But I could cover it with the EF-70 200 so that's probably the logical way to go

I'm sure an R7 would give better quality with this lens than an R5 + a third-party TC.

An R7 isn't going to be on the cards. Investigated to death. Just not the machine for us.

R5II or better still something with a big jump in resolution. Whichever it will cause a lot of process changes and validation so I won't be in a hurry to spend as soon as it arrives. If it needs a different grip for instance then that's a bit more of a head scratcher.

All that said I would think you are right. But it's back to opportunity - we have one thing not the other.

TCs have their place with long lenses if you're trying to get more reach, but they don't really work with standard lenses.

I appreciate what your saying. We currently use a TC1.4 and from what I am reading from you it's likely not always the best optical decision.

Appreciate all the effort you have gone to at a weekend to help me. If you are ever at a loose end in West Yorkshire I'm sure we would benefit from you knowledge.