[Docrwm]

You so helpful No worries I got it

We're here to help. Let me know if the burden gets to be too great.

[snostorm]

For what it's worth, I've got a JJC tripod collar for the Canon 200 f4 L, and it measures 65mm inside diameter. It fits the DA 55-300 and is a tight fit for the FA* 300 f4.5. It's made of plastic, and though it resembles a lot of these Chinese models, it has an aluminum knurled knob instead of the fluted one these show. The one's linked on ebay show a 66mm inside diameter, but this would not be a problem if the outside diameter of the adapter is 65mm, a little electrical tape, and you're all set -- slightly bigger is definitely much better than too small. The way these lock, you can't really grind the locking groove to make it looser.

I'm thinking that one of the ones I have will work, and if my dealer ever gets an adapter in, I'll be able to report.

Scott.

[baro-nite]

The few posts I have seen that had positive things to say about Pentax parts all involved a telephone call as I recall.

My two attempts (about a year ago, then yesterday) to contact them both involved calling and leaving a message. No reply last year, and no reply yet this year.

[Docrwm]

My two attempts (about a year ago, then yesterday) to contact them both involved calling and leaving a message. No reply last year, and no reply yet this year.

I did say "few"......

The way I, inadvertently, got a part from Pentax USA was to email Pentax Canada after getting lied to by Pentax USA's sales office. Seems that email embarassed Pentax USA. Seriously, it's really a sad state of affairs when a customer calls ready to buy something and the sales/support people don't even reply.

[panoguy]

At $379 it will probably be only slightly more than the Pentax clamp

Well, for that $379 you also get an indexing panohead and clamp... can't imagine that part would be needed by everyone!

[crewl1]

Had a chance to take the Pentax adapter out for a quick spin for telephoto application.

The adapter is well made and it feels solid going onto the lens and Q.

The smooth (no-click) aperture ring was not a problem since I was working from a tripod and gimbal. I'll be testing hand held later this week to see if it can be accidentally moved.

I compared the adapter against my 'painted internals' Fotodiox, and I cannot tell a difference in IQ, but I am on a work laptop so don't have access to any editing tools to look closely. Maybe one of you can spot a difference.

I did experience an advantage from the Pentax in that I was able to photograph a swimming pelican that I was tracking with the gimbal, and the leaf shutter eliminated the jello effect that I would normally get from the electronic shutter.

The target for the comparison is a signpost about 60 yards away, you can see it in the iphone shot as a yellow stick on the bank.



DA*300 with Fotodiox (I did not notice this one was a little more open than the other so background has more blur, sorry)


DA*300 with Pentax


Sigma 70-200 with Fotodiox (made effort to match these on aperture, but since there is no indication I had to go by resulting shutter speed, but I think I got it close)


Sigma 70-200 with Pentax


So for now I think if you paint your cheap adapter you should be good as far as IQ, the advantages of the Pentax are in the leaf shutter for eliminating jello and for use with flash such as in Macro application.

I did find that the max speed of the Pentax is 1/1000 - I found this when I had a period of bright sunshine and I tried to up the shutter speed and it stopped at 1/1000. I then had to close the aperture to bring the exposure in range, as I was already at ISO 125. This could be an issue on very sunny days possibly since the aperture needs to be kept fairly open to avoid diffraction.

[crewl1]

Back in town now and had a chance to process some of the bird shots from the comparison outing.
Differences in lighting were due to the sun coming in and out of clouds.

The Fotodiox + DA*300


The Pentax adapter + DA*300


In controlled conditions on a tripod I don't really see a difference between the results you can get from the 3rd party vs the Pentax, as long as you eliminate internal reflections from the 3rd party adapter by painting the inside.

One advantage for the Pentax is the ability to cancel the jello effect, since the shutter closes in an instant, which is a factor in hand held shooting.
The other reason to get it is the ability to shoot at higher shutter speeds with flash vs. the 1/13 max with 3d party adapters. This is important for macro.
Both of these reasons make it worth the price IMO

The other difference I'll reiterate is in max shutter speed using the 3rd party adapter, which will let you go as high as 1/8000, vs the Pentax which only lets you set 1/1000 max.

---

Last edited by crewl1; 12-01-2012 at 01:13 PM.

[drougge]

The other difference I'll reiterate is in max shutter speed using the 3rd party adapter, which will let you go as high as 1/8000, vs the Pentax which only lets you set 1/1000 max.

You can use the electronic shutter with any lens(adapter), just set custom function 13 ("Electronic shutter") to 2. (Despite the wording in the settings it will still use the lens shutter if the speed is slow enough.)

[crewl1]

You can use the electronic shutter with any lens(adapter), just set custom function 13 ("Electronic shutter") to 2. (Despite the wording in the settings it will still use the lens shutter if the speed is slow enough.)

Cool, thanks for that info drougge

[crewl1]

I'm measuring the outside diameter of the adapter where a ring could be mounted at 65mm. Can anyone confirm? If so I am wondering if this unit will work, perhaps with a bit thicker rubber? Tripod Collar Mount Ring A(W) for Canon EF 70-200mm f/4L IS USM Lens | eBay

So I screwed up and measured the adapter wrong, it is actually more like 68mm plus, so the tripod ring I ordered is too small.

The good news is that the rings fits nicely on the DFA 100, which is what I mainly wanted to use it for (macro.)

So if you decide to get a tripod ring for the adapter, take note that you should not order a 65mm ring, rather take your own measurements and get the larger one required. Do not rely on any numbers I quote, sorry.

[Docrwm]

So I screwed up and measured the adapter wrong, it is actually more like 68mm plus, so the tripod ring I ordered is too small.

The good news is that the rings fits nicely on the DFA 100, which is what I mainly wanted to use it for (macro.)

So if you decide to get a tripod ring for the adapter, take note that you should not order a 65mm ring, rather take your own measurements and get the larger one required. Do not rely on any numbers I quote, sorry.

Thanks for the update. You might add the adapter to the accessories database with a note that it fits the DFA100 so nicely. Glad it wasn't a total waste for you.

[crewl1]

You might add the adapter to the accessories database with a note that it fits the DFA100 so nicely.

Will do Doc, will get to it in a couple of days. What category do you suggest? Tripod acc, Lens acc or other?

[Docrwm]

Will do Doc, will get to it in a couple of days. What category do you suggest? Tripod acc, Lens acc or other?

I'd say Tripod Accessory personally. I think its only use is with a tripod (or mono).

[pihe]

A quick question (don't want to open a thread for it): how do you protect your adapter against cold? I also own the OEM Pentax Q-K adapter and I have noticed that it stops working below 0 Celsius degrees. It's pretty cold now in Hungary and wanted to use my Sigma 105 to take macro shots of snowflakes but after 10 exposures the adapter said 'no'. While it's solid metal, it gets cold very quickly... Do you have any idea about keeping it warm?

[barondla]

Pihe, didn't expect cold to be such a problem for the adapter. Could it be the battery in the camera having the problem? That is something I would expect. In these conditions, will the camera fire if you take the adapter off and use a Q lens?
thanks
barondla