View Full Version : 2x teleconverter
incisor
22nd October 2016, 06:06 PM
I came across a 2x teleconverter today
windy as hell here at the moment and quite dull so not really conducive to using said converter on the end of a 300mm lens to take pics of birds swinging on a branch :p
maybe tomorrow will be better.
so a 2x on an fx 300mm lens on a dx should lose me some sharpness and speed but it should get me closer but will it be usable..
i did what i could to work out a way to use it but the wind defeated me and all i got was blurry pics :p
dullbird
22nd October 2016, 07:21 PM
Is it the newer x2 Nikon or a third party one. 
I believe the older x2 nikon was terrible but reports are the newer one is much more improved
Bytemrk
22nd October 2016, 07:29 PM
I came across a 2x teleconverter today
windy as hell here at the moment and quite dull so not really conducive to using said converter on the end of a 300mm lens to take pics of birds swinging on a branch :p
maybe tomorrow will be better.
so a 2x on an fx 300mm lens on a dx should lose me some sharpness and speed but it should get me closer but will it be usable..
i did what i could to work out a way to use it but the wind defeated me and all i got was blurry pics :p
900mm equivalent ...... gonna have to hold that old Soligor steady Dave..:D
 Looking forward to the results... some of your recent birds have been really sharp....it's obviously a good old chuck of glass.
scarry
22nd October 2016, 09:45 PM
If it is similar to Cannon,remember to fit it to camera first,then fit to lense.
Doing it the other way around,it won't work very well.
I found this out the hard way.:(
Surprisingly,our 1.4X actually takes very good pics.
Pedro_The_Swift
23rd October 2016, 07:07 AM
in case you were wondering Inc,, :angel:
Stacking Five 2x Teleconverters to Create a Ridiculous 9600mm Lens (http://petapixel.com/2015/02/05/stacking-five-2x-teleconverters-create-ridiculous-9600mm-lens/)
incisor
23rd October 2016, 09:25 AM
Waiting.... 
https://www.aulro.com/afvb/images/imported/2016/10/242.jpg
https://www.aulro.com/afvb/images/imported/2016/10/243.jpg
800 iso and 1/8th second to get a decent exposure at the moment..
the teleconverter locks it into f4
Is an old soligar em mount unit
incisor
23rd October 2016, 06:08 PM
might work better on solid ground :p
nothing i took was anything near acceptable so i'll have to spend a lot more time tinkering....
was barely okay at 600mm which is where this is taken at
https://www.aulro.com/afvb/images/imported/2016/10/220.jpg (https://flic.kr/p/Mw2Anj)
900mm (https://flic.kr/p/Mw2Anj) by Dave Blears (https://www.flickr.com/photos/niknodave/), on Flickr
dullbird
26th October 2016, 01:59 PM
Its known that teles can bring on some softness in the images just bare that in mind
AK83
27th October 2016, 04:30 PM
two points to consider.
1. (and probably the main reason for image quality degradation) your tripod and head setup. There's a 99.9% chance that it's not up to the job of steadying that magnification factor. 
2. lens(what lens are you using?) If the taking lens is not producing an optimal image, then the teleconverter creates a sub optimal image, of a sub optimal image!
Camera appears too be a D7000. If so, then this camera has the ability for either or exposure delay and or mirror lockup exposure.
You need to use those features to assess the quality of the resultant images.
If not, all you will be doing is assessing that the manfrotto tripod and head used (as shown in the image) are not up to the task of eliminating vibrations.
if you want to see those vibes, set your camera to liveview mode, or movie mode.
Liveview mode will only allow you to see the vibrations caused by the support structure in realtime and that's it.
Shoot a short (say 30s) video and watch how the vibrations come and go with irregularity. You can do this in the comfort  of your PC desk chair! :D
I'm not 100% sure how the D7000 uses Lv mode, but I have a vague recollection that it's similar to the D300 .. which is utterly crap!
Lv mode bypasses the mirror relaying mechanism, so that what you see is directly from the sensors readout. But what the D300 does(and I think the D7K too) is to flip the mirror down and then up again just prior to the Lv exposure. 
(why Nikon implemented this system defies comprehension!)
That is, Lv mode should otherwise be a great way to  eliminate mirror slap, but Nikon engineers saw fit to  double it up instead the way they set it up!
So Lv mode may not help at all to eliminate mirror slap. Hence why exposure delay and or mirror lockup mode may be needed.
Note tho, even if you do eliminate mirror slap(which will produce most of the vibrations) it doesn't eliminate shutter shock, that is the first curtains slap at the end of its travel.
Also: you said it locks the camera to f/4 :confused:
This kind'a doesn't make sense(other than ... )
it doesnt' make sense because a 2x teleconverter will force your lens down by two stops to it's most open aperture setting.
So, if you xx-300mm lens had a f/5.6 aperture setting, then the TC will set it's maximum aperture setting to f/11!
if you say that it's locked at f/4, then your 300mm lens must have a max aperture of f/2. Now that is one super duper awesome hell of a 300mm lens .. and only Nikon made such a monster about 30 odd years ago and they now sell for about $30K for a junked version!
This is where the "other than" comment comes in.
If the TC is an old timer non cpu/ non connected type for an old lens, then what is most likely happening is that you have set up an old lens in the non CPU lens feature which is probably an f/4 lens of some type.
The camera doesn't know what lens type is attached(as it's not connected) and a lens has been programmed into the non CPU lens area.
So the camera thinks this lens is now that programmed in lens.
For it to work 'properly'(in the above sense) you will need to set the non CPU lens data correctly.
So what you'd do, if you want to use the lens at 600mm and wide open setting is to set the non CPU lens data as: Focal length- 600mm and Aperture- f/11.
If the aperture is coupled, then as you stop it down a slight smidge, it will show you the new aperture indication in the camera too.
But you won't get any focal length changes.
some tips:
if you want focal length values, you set up some more in non CPU lens data area, and also the associated max aperture values.
Use the Auto high ISO feature and try to shoot in either manual mode or shutter priority mode.
With these focal lengths on questionable support high shutter speeds are essential!
More handy tips. 
Try some tests at a focal length just short of max.
Most of those zoom lenses don't work their best at max focal length.
You may see better IQ at say 250mm (of a max 300mm).
or of the lens has a max of say 400mm, then try 300mm.
Don't get trigger happy and max everything out. Sometimes it makes all the difference!
And try one stop down. 
So your lens is probably f/5.6, and the TC will give an effective and real f/11.
So set the aperture(if you can) to f/8 .. that little bit more contrast can make the world of difference.
Does the lens have an aperture ring for you to set?
final hint/tip: Dont' shoot tree branches/leaves/birds/flowers/any movable subject matter.
While they look nicer, all you may be doing is showing us how much they each move in 1/8s(which is very slow).
Shoot totally static and very reflective subject matter if you want to assess the lens and TCs ability.
The wire caging on the trailer is ideal subject matter.
it's fine enough to show detail and bright enough to allow you to shoot at a minimum 1/600s + shutter speeds .. faster is better!
(same with the texture of the cream part of the Alu shed!!)
And when you do make any exposures, set the camera to spot meter only(it's tech matter in this situation anyhow!) and give it about -0.3 to -0.5 Ev under exposure.
exposure can have a bearing on how detailed resolution can appear to the human eye.
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