sigma fp l + SIRUI 35 mm T2.9 Anamorphic : A process for de-squeezing and lens correction

[exc01]

Hello!

We use a combination of sigma fp l + SIRUI 35 mm T2.9 Anamorphic (SIRUI Venus 35mm T2.9 1.6x anamorphic full frame lens - for dive) for video and photo. Now I am writing concerning the photo application. The process of de-squeezing in Photoshop and the following lens correction process seem to be non-optimal. After 1.6x de-squeezing in Image Size the image, the image is distorted at the right and left sides. So we correct the lenses in Photoshop (Filter - Lens Correction - Custom - Remove Distortion). If I set it to ca. -15/-12, then the verticals are fine, but the horizon is curvy. And if I let the Geometric Distortion 0, then I have the horizon straight, but the sides are distorted. So the question is - what do we do wrong?
If I change the sensor setting from 3:2 to 16:9, the same thing happens. (BTW What does it bring, to switch from 3:2 to 16:9 using this lens?)

The second thing: we do need the image size of 2.8:1 or at least 2.4:1. If this SIRUI 35 mm T2.9 Anamorphic doesn't offer an image with proper optical proportions, would be a solution to take a Sigma 35mm F1,4 DG HSM | Art (Übersicht) and just crop the 16:9 image to 2.8:1 or 2.4:1?

Thanks in advance for your answers!

BR + thanks,
Tim

 

[declanjames89]

Hello!

We use a combination of sigma fp l + SIRUI 35 mm T2.9 Anamorphic (SIRUI Venus 35mm T2.9 1.6x anamorphic full frame lens - for dive) for video and photo. Now I am writing concerning the photo application. The process of de-squeezing in Photoshop and the following lens correction process seem to be non-optimal. After 1.6x de-squeezing in Image Size the image, the image is distorted at the right and left sides. So we correct the lenses in Photoshop (Filter - Lens Correction - Custom - Remove Distortion). If I set it to ca. -15/-12, then the verticals are fine, but the horizon is curvy. And if I let the Geometric Distortion 0, then I have the horizon straight, but the sides are distorted. So the question is - what do we do wrong?
If I change the sensor setting from 3:2 to 16:9, the same thing happens. (BTW What does it bring, to switch from 3:2 to 16:9 using this lens?)

The second thing: we do need the image size of 2.8:1 or at least 2.4:1. If this SIRUI 35 mm T2.9 Anamorphic doesn't offer an image with proper optical proportions, would be a solution to take a Sigma 35mm F1,4 DG HSM | Art (Übersicht) and just crop the 16:9 image to 2.8:1 or 2.4:1?

Thanks in advance for your answers!

BR + thanks,
Tim

It seems like you're facing some challenges with the de-squeezing and lens correction process in Photoshop for your Sigma fp L with the SIRUI 35mm T2.9 Anamorphic lens. When you de-squeeze the image by 1.6x, it's causing distortion at the sides when you try to correct it using the lens correction tool.

To address the issue where correcting the lens distortion either affects the verticals or the horizon, you might want to try adjusting the "Aspect Ratio" and "Scale" settings in the Lens Correction dialog box in Photoshop. By tweaking these settings along with the distortion correction, you may find a balance that straightens both the horizon and the sides without distortion.

Switching from a 3:2 sensor setting to 16:9 with this lens can affect the composition of your shots. The 16:9 aspect ratio provides a wider field of view, which can be beneficial for capturing more in your frame, especially for video content.

If you require an image size of 2.8:1 or 2.4:1 and the SIRUI 35mm T2.9 Anamorphic lens isn't providing the desired optical proportions, using a Sigma 35mm F1.4 DG HSM | Art lens and cropping the 16:9 image to achieve the desired aspect ratio could be a viable solution. This way, you can maintain the optical quality of the Sigma lens while cropping the image to meet your specific aspect ratio requirements.