zvonimiri Posted May 17 Posted May 17 Hello All, Considering to purchase the Kenko 1.4x Teleplus Pro 300 DGX teleconverter for my Canon 8-15mm fisheye lens. I know that without the teleconverter at 15mm it is a 180 degree diagonal fisheye view and at 8mm it is a 180 degree circular fisheye view. Does anyone know the FOV degrees when the teleconverter is added? Especially at 21mm (15mm on a full frame sensor with the teleconverter added) and at each other focal length. Many thanks! 1
Davide DB Posted May 17 Posted May 17 Hi Zvonimiri, I dont' know its FOV but it's a popular choice and maybe someone will chime in. in the meantime you can check these two threads (if you didn't already):
Guest Posted May 17 Posted May 17 8 hours ago, zvonimiri said: Hello All, Considering to purchase the Kenko 1.4x Teleplus Pro 300 DGX teleconverter for my Canon 8-15mm fisheye lens. I know that without the teleconverter at 15mm it is a 180 degree diagonal fisheye view and at 8mm it is a 180 degree circular fisheye view. Does anyone know the FOV degrees when the teleconverter is added? Especially at 21mm (15mm on a full frame sensor with the teleconverter added) and at each other focal length. Many thanks! Precise measurements are not easy however it is around 120 degrees diagonal at 21mm Do not buy the teleplus pro 300 dgx that is now obsolete there is a new version
Tom Kline Posted May 17 Posted May 17 I can confirm that the Canon 8-15mm lens has focus breathing with concurrent change in angle of view.
Guest Posted May 18 Posted May 18 9 hours ago, Tom Kline said: I can confirm that the Canon 8-15mm lens has focus breathing with concurrent change in angle of view. Hi Tom all lenses have focus breathing what bothers you specifically with the 8-15?
Tom Kline Posted May 19 Posted May 19 Nothing bothers me it is just very obvious when reviewing images in Lightroom and moving through them quickly in the 'filmstrip" or using arrow keys when they are taken with a stationary camera such as my salmon shoots in streams.
Guest Posted May 20 Posted May 20 10 hours ago, Tom Kline said: Nothing bothers me it is just very obvious when reviewing images in Lightroom and moving through them quickly in the 'filmstrip" or using arrow keys when they are taken with a stationary camera such as my salmon shoots in streams. Are you not using fixed focus? If your dome is not too small you can achieve depth of field all the way through. The focus position in my set up moves around 15cm and for close shots even less Not familiar with this kind of trap but I would think autofocus can be really tricky
Adventurer Posted May 20 Posted May 20 32 minutes ago, Interceptor121 said: 11 hours ago, Tom Kline said: Are you not using fixed focus? If your dome is not too small you can achieve depth of field all the way through. The focus position in my set up moves around 15cm Exactly + great advice 👍 Could you add if you mean 1.) 15cm Virtual-Image/EXIFdata distance 2.) 15cm from dome glas 3.) 15cm from lens front 4.) 15cm from sensor plane *2-4 measured with a ruler in space time 😉
Guest Posted May 20 Posted May 20 3 hours ago, Adventurer said: Exactly + great advice 👍 Could you add if you mean 1.) 15cm Virtual-Image/EXIFdata distance 2.) 15cm from dome glas 3.) 15cm from lens front 4.) 15cm from sensor plane *2-4 measured with a ruler in space time 😉 Focus point is always measured from the sensor focal plane regardless of any port set up
zvonimiri Posted May 20 Author Posted May 20 Many thanks @Davide DB for the recommendations! I have not seen the second discussion and it was very useful. I agree with Interceptor121 that the default setup for the Canon 8-15mm should be with the 1.4x convertor as the 8mm circular fisheye look is more of a luxury rather than a necessity. Many thank as well @Interceptor121 ! I had a look at the FOV calculation for fisheye lenses and saw that it requires too much of a technical involvement for me to go with that route 🙂 Knowing the range is between 174 to 124 would suffice (as per your article) . Just completed the first dive weekend with my new set up this weekend. It is a R6 mark II with Nauticam housing. Nauticam lists the Teleplus Pro 300 DGX version on their port charts and they are probably not updated yet. You also mention that there is a need for only a 2 cm extension with the HD PRO as well. I will go with the HD Pro version as per your recommendation. Many thanks for the money saved! 1
Guest Posted May 20 Posted May 20 20 minutes ago, zvonimiri said: Many thanks @Davide DB for the recommendations! I have not seen the second discussion and it was very useful. I agree with Interceptor121 that the default setup for the Canon 8-15mm should be with the 1.4x convertor as the 8mm circular fisheye look is more of a luxury rather than a necessity. Many thank as well @Interceptor121 ! I had a look at the FOV calculation for fisheye lenses and saw that it requires too much of a technical involvement for me to go with that route 🙂 Knowing the range is between 174 to 124 would suffice (as per your article) . Just completed the first dive weekend with my new set up this weekend. It is a R6 mark II with Nauticam housing. Nauticam lists the Teleplus Pro 300 DGX version on their port charts and they are probably not updated yet. You also mention that there is a need for only a 2 cm extension with the HD PRO as well. I will go with the HD Pro version as per your recommendation. Many thanks for the money saved! The tele plus pro 300 is obsolete the new hdx dg pro top of the range can be found for competitive prices here in UK https://kenkoglobal.com/product/teleplus_hd_pro_1_4x_dgx/ both require an additional 20mm extension
John E Posted May 20 Posted May 20 One of the advantages of the Sony A7RV is versatility due to the sensor pixel density being like the A6700. With combined port extensions where 20mm can be removed, this means the rig can be used with the Kenko and a larger port for best full frame picture quality, but also handily can be used without the Kenko and with a small fisheye port and shorter port when minimum housing size is needed, such as when freediving. Then it can be used in full frame mode or the 26Mp APS-C frame size with zoom range. I am not sure if it better to use the APS-C mode on the camera or stay with full frame and just crop. Maybe someone can confirm? I don't think it makes any difference in picture quality but having the APS-C mode on the function button menu makes it very quick to switch to help framing composition.
ChipBPhoto Posted May 20 Posted May 20 2 hours ago, John E said: I am not sure if it better to use the APS-C mode on the camera or stay with full frame and just crop. Maybe someone can confirm? I don't think it makes any difference in picture quality but having the APS-C mode on the function button menu makes it very quick to switch to help framing composition. Hey John - selecting APS-C or cropping the FF in post is exactly the same thing. The only difference is when in APS-C mode only the smaller portion of the sensor is used. This results in the lower resolution. Agreed that using APS-C can def help with composition. The only downside is if the desired final frame is larger than the smaller activated portion of the sensor. I personally normally work in the higher res FF mode and crop in post as needed. This allows the most options for the final product. Hope this helps - Chip
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