[dark64]

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Hi. I have a Pentax 55-300 f/5.6-6.3 PLM lense. I like to shoot birds and i feel like I need some more focal lenghts. There are three options but only two for me - buy a new lense ( i don't want to because of their size! ) , use rear or front teleconverter. Today i checked rear Pentax 1.4 with my lense and AF working well ( with f/9,5 ) . Only problem is pirce - it's preety damn expensive in here.

In the other hand we have Nikon TC-DC58C - front teleconverter. I couldn't test it. Internet reviews are preety good but almost all of the users use them with compacts cameras. There also other TC like or DCR-2025 PRO or Sony 1.7x VCL-DH1758

The Nikon is the cheapest one.

Any opinions?

[Adam]

If you want good AF results and the best possible image quality, you'll want to use the Pentax DA 1.4x teleconverter. The combo's AF might struggle due to the narrow aperture, but should be OK in good light on the K-3 / K-S2 or newer.

[boriscleto]

TANSTAAFL. The 1.4 TC will get you to 420mm, but it's F/9.5...

A front TC is really a choice of last resort. Which is why most of the users are compact camera users...

I used a 1.4 TC with a DA L 55-300. It was ok for a walking around solution, but I use a Sigma 150-500 now...

[UncleVanya]

Read a similar discussion here:

https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/285267-fron...y-vs-rear.html

---------- Post added 12-30-16 at 10:15 AM ----------

Read a similar discussion here:

https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/285267-fron...y-vs-rear.html

Since that thread my research seems to suggest the major use cases of front converters is fixed lens (zoom or prime) systems. 35mm rangefinders with fixed lenses, small digital compact cameras.

[ramseybuckeye]

Spend more money or learn to get closer to the birds. There was a good discussion on here a couple of years ago about using hunting blinds. If you get anywhere that you casn sit in a car and shoot it can help, birds don't seem to mind that as much as a person on foot.

[THoog]

A number of issues here:

- From what I can tell, the TC-DC58C is a Canon teleconverter, not Nikon. The Nikon equivalent appears to be the TC-E2, but it only has a 28mm rear thread. While the Canon has a 58mm rear thread, it is intended for fixed-lens compacts and bridge cameras with much smaller sensors. Any reviews will be in that context, and not a good indicator of how it might perform on a DSLR lens. The same can be said for most front-mount TCs . To be honest, the "brag" pictures I've seen with a $200+ front-mount TC on various bridge cameras didn't impress me. I think I could have done as well by cropping a shot from the 55-300.

- While the DA 55-300 is a better-than-average consumer zoom lens, it's still only better-than-average. Success with a teleconverter depends on the quality of the host lens and the quality of the TC. Putting the cheapest 2x TC you can find on the 55-300 will turn it into a very slow bargain-basement zoom, with IQ to match.

- Any 2x TC on the 55-300 is going to lose about two stops of light because of all the extra glass. Unless you are shooting in bright desert conditions, you probably won't have enough light to autofocus reliably.

- Long term, I'd recommend looking for a good used Sigma 500mm zoom, or something like that. Until then, if the Pentax 1.4x TC is outside your budget, you could look for a used Kenko 1.4x or 1.5x TC. They appear from time to time under a number of different brands.

[rrstuff]

It will be difficult to go longer than 300mm, with good quality and reasonable budget. Probably the cheapest option is one of the old sigmas, 135-400, 400mm AF APO, 170-500.

[marcusBMG]

It will be difficult to go longer than 300mm, with good quality and reasonable budget.

....with AF!
There are numerous MF options. Check out some of cleaverx pics with smc 500mm and smc-A 400mm eg here.
I have posted pics in the 300mm lens club with a variety of MF lenses.

[cyclone3d]

Here are a couple options on eBay:

650-2600mm lens setup (manual):
Opteka 650-2600mm HD Telephoto Lens for Pentax K-01 K01 K-3 K3 K-5 K5 II IIs K-7 | eBay

Kenko 2x AF teleconverter:
2470#J Kenko MC7 P-AF 2X Teleplus DG Teleconverter For Pentax Excellent+++ | eBay

[marcusBMG]

50-2600mm lens setup (manual):

see my review of the similar 420-800mm. I expect that the 650-1300's are even worse!

Opteka ( Top-max, kelda etc ) 420-800mm f8.3-16 Lens Reviews - Miscellaneous Lenses - Pentax Lens Review Database

I've tried several 2x TC's including the well rated adaptall 01F, vivitar macro TC. IME the sort of lens you can use them with with reasonable success is a high quality 300mm f2.8. Otherwise I find that the loss of 2 stops and the magnification of aberrations = its all a bit of a dead loss.

[UncleVanya]

see my review of the similar 420-800mm. I expect that the 650-1300's are even worse!

Opteka ( Top-max, kelda etc ) 420-800mm f8.3-16 Lens Reviews - Miscellaneous Lenses - Pentax Lens Review Database

I've tried several 2x TC's including the well rated adaptall 01F, vivitar macro TC. IME the sort of lens you can use them with with reasonable success is a high quality 300mm f2.8. Otherwise I find that the loss of 2 stops and the magnification of aberrations = its all a bit of a dead loss.

The FA* 300 and the DA* 60-250 are both very adaptable to 1.4x and even 1.7x adapters but your point is accurate - the more magnification added the higher the quality you should start with to get good results. One of our members here uses the DA* 200 with the 1.4 and 1.7x TC's stacked and gets good results.

The DA 55-300 has some people who swear by using it with the 1.4x but I have no experience doing that. I own both but have never considered trying due to the slow speed already imposed by the lens.

[cyclone3d]

see my review of the similar 420-800mm. I expect that the 650-1300's are even worse!

Opteka ( Top-max, kelda etc ) 420-800mm f8.3-16 Lens Reviews - Miscellaneous Lenses - Pentax Lens Review Database

I've tried several 2x TC's including the well rated adaptall 01F, vivitar macro TC. IME the sort of lens you can use them with with reasonable success is a high quality 300mm f2.8. Otherwise I find that the loss of 2 stops and the magnification of aberrations = its all a bit of a dead loss.

Yeah.. not surprising about the image quality on the Opteka lenses.

However.. I do have one of those Vivitar 2x macro teleconverters and it seems to work pretty well with my converted Olympus 55mm 1.2 lens. I haven't really tried it on other lenses yet.

[dark64]

And any of those mirror lenses are worh of buying? The're preety cheap and small for such focal lenghts

[boriscleto]

And any of those mirror lenses are worh of buying? The're preety cheap and small for such focal lenghts

Not any of the newer ones.

Some older mirrors get ok reviews if you can live with the donut bokeh.

Sigma QX 500mm F8 mirror Lens Reviews - Sigma Lenses - Pentax Lens Review Database

The 350mm seems to rare as hens teeth. I would love one for the Q...(there are 3 on eBay ranging from $400 to $750, insane)
Tamron Adaptall-2 SP 350mm f/5.6 (mirror) (06B) Lens Reviews - Tamron Adaptall Lenses - Pentax Lens Review Database

Tamron Adaptall 500mm f/8 SP Mirror (55B) Lens Reviews - Tamron Adaptall Lenses - Pentax Lens Review Database

Tamron Adaptall-2 SP 500mm f/8 Mirror (55BB) Lens Reviews - Tamron Adaptall Lenses - Pentax Lens Review Database

[UncleVanya]

The best review of mirror lenses I recall reading said it best. The depth of field is razor thin and manually focusing these on a digital camera is a pain. The only AF version known is the Sony A mount Minolta one. If these came with good reliable AF they would be more interesting.