# Mergius: HDR Photo & Tone map — HDR, tone mapp, photo adjust

> Professional HDR photo merging and tone mapping tool with advanced features. (iPhone/iPad app by Roman Sisik.)

- Source: https://appshunter.io/ios/app/mergius-hdr-photo-and-tone-map/id6749581377 (this page in markdown: same URL + `.md`)
- Developer: [Roman Sisik](https://appshunter.io/developer/1704315884)
- Category: Photo & Video, Utilities
- Price: Free with in-app purchases
- Age rating: 4+
- Requires: iOS 17.6 · 27 MB
- Languages: American English
- Released: 2025-08-13
- Data updated: 2026-08-12
- Monetization: free with in-app purchases
- User reviews in markdown: https://appshunter.io/ios/app/mergius-hdr-photo-and-tone-map/id6749581377/reviews.md

## What is Mergius?

Unlock the full potential of your photos! Pro HDR Fusion lets you effortlessly merge multiple exposures into a single, stunning High Dynamic Range image.

Experience true creative control with professional-grade tools right on your device. Whether you're a photographer looking for the perfect HDR merge or a VFX artist working with professional formats, our app is built for a powerful and precise workflow.

Key Features:

HDR & Exposure Fusion: Combine multiple photos into one perfectly exposed image. Choose between the classic Robertson & Debevec HDR algorithm or the seamless Mertens Fusion method.

Perfect Alignment: Our automatic image alignment ensures your photos are sharp and ghost-free before merging, even when shooting handheld.

Pro File Support: Natively open, modify, and export high-quality OpenEXR (.exr) and Radiance (.hdr) files.

Advanced Tone Mapping: Sculpt the final look with a suite of professional tone mapping operators: Reinhard, Drago, Mantiuk, Linear, and Normalize.

Final Adjustments: Polish your masterpiece with Auto White Balance, Brightness/Contrast, and Saturation controls.

Flexible Export: Save your work as a high-quality JPEG or PNG for easy sharing, or export back to .exr or .hdr to maintain the full dynamic range for your professional pipeline.

Download now and create breathtaking HDR images with unparalleled power and quality!

Paid features:
- automatic image alignment
- Robertson hdr algorithm
- Reinhard, Drago, and Mantiuk tone-mapping algorithm
- Auto White Balance
- Saturation adjustment
- shadows & highlights, vibrance effect, punchy colors effect
- capturing bracketed image directly with camera
- Export to .exr/.hdr formats

Terms of use:
https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

## Key features

- HDR and Exposure Fusion
- Automatic Image Alignment
- Pro File Support (.exr, .hdr)
- Advanced Tone Mapping Operators
- Final Adjustments (White Balance, Brightness)
- Flexible Export Options

## Pricing and in-app purchases

Base price: Free.

**Subscriptions**

| Subscription | Price | Period |
| --- | --- | --- |
| Mergius Pro (Annual) | $29.99 | per year |
| Unlock Premium Features | $4.99 | per 7 days |


## Recent user reviews (2 of 2)

All indexed reviews: https://appshunter.io/ios/app/mergius-hdr-photo-and-tone-map/id6749581377/reviews.md

### 1/5 — Doesn’t work

*2026-03-02*

Kept crashing when I’d try to add photos

**Developer response:** I'm not able to replicate your issue on my devices. Can you provide more information? What was the format and size of the image files. What exactly did you tap inside the app? Were there any error messages? If possible, can you provide the image samples? You can reply directly to my email roman@sisik.eu

### 1/5 — Pretty Dismal

*2026-01-24*

Doesn’t export.

**Developer response:** Don't understand. Is the export to radiance hdr or OpenEXR not working for you? Can you provide more information about your issue? Is there an error message? What exactly are you trying to do? You can send information directly roman@sisik.eu. If I find any issues, I'll try to fix those as soon as possible.

## Frequently asked questions about Mergius

### What is Mergius used for?

Mergius is used to merge multiple photos into a single High Dynamic Range (HDR) image and apply advanced tone mapping for professional-looking results. It also supports professional file formats like OpenEXR and Radiance.

### Does Mergius offer a free trial?

Yes, Mergius offers a free trial for its premium features. The 'Unlock Premium Features' subscription plan includes a 3-day free trial before the $4.99/week charge.

### What are the paid features in Mergius?

Paid features include automatic image alignment, the Robertson HDR algorithm, specific tone-mapping algorithms (Reinhard, Drago, Mantiuk), Auto White Balance, saturation adjustment, shadow/highlight controls, and export to .exr/.hdr formats.

### How often is Mergius updated?

The app was last updated on November 22, 2025, indicating a recent update. The latest version is 1.5.

### What devices is Mergius available on?

Mergius is available on iPhone and iPad devices, as indicated by the supported devices list.

### What is the age rating for Mergius?

Mergius has an age rating of 4+, making it suitable for a wide range of users.

### Can I cancel my Mergius subscription?

Yes, users can typically cancel subscriptions through their device's app store settings. The subscription plans are billed weekly or annually.

### Does Mergius have ads?

No, Mergius does not contain advertisements. The app is free to download with optional in-app purchases for premium features.

## Version history (last 5 releases)

### 1.5 — 2025-11-22

- fixed crashes 
- fixed swapped colors

### 1.4 — 2025-10-03

Added new post-processing effects - shadows & highlights, vibrance, and punchy colors. Added option to capture bracketed photos automatically.

### 1.2 — 2025-08-29

- added more adjustment effects
- fixed issues with extracting exposure information from some images
- fixed some crashes and other issues

### 1.1 — 2025-08-19

Fixed issues

### 1.0 — 2025-08-13

No release notes.

## Apps similar to Mergius

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [WeRetouche – HDR Real Estate](https://appshunter.io/ios/app/weretouche-hdr-real-estate/id6751543564) | — | Free | Photo & Video |
| [HDR Easy](https://appshunter.io/ios/app/hdr-easy/id6745524653) | 4.5 (2) | Free | Photo & Video |
| [LiGHTBOX - HDR Toys](https://appshunter.io/ios/app/lightbox-hdr-toys/id6747686037) | 5.0 (1) | Free | Photo & Video |
| [Simple HDR](https://appshunter.io/ios/app/simple-hdr/id1035541353) | 2.7 (7) | $9.99 | Photo & Video |
| [toHDR](https://appshunter.io/ios/app/tohdr/id6746218392) | — | Free | Photo & Video |
| [MagiCam: AI Photo Editor](https://appshunter.io/ios/app/magicam-ai-photo-editor/id6480352051) | — | Free | Photo & Video |

## More apps by Roman Sisik

- [Bugjaeger - Mobile ADB](https://appshunter.io/ios/app/bugjaeger-mobile-adb/id6463413200)
- [Pano Stitch & Crop](https://appshunter.io/ios/app/pano-stitch-and-crop/id6501949555)
- [Taguvo: QR & Barcode generator](https://appshunter.io/ios/app/taguvo-qr-and-barcode-generator/id6752238221)
- [Duplila: Screen Mirroring](https://appshunter.io/ios/app/duplila-screen-mirroring/id6754455571)

All apps by Roman Sisik: https://appshunter.io/developer/1704315884

## Related topics

[photo hdr](https://appshunter.io/ios/topics/photo-hdr) · [hdr merge](https://appshunter.io/ios/topics/hdr-merge) · [hdr photo lab](https://appshunter.io/ios/topics/hdr-photo-lab) · [hdr max](https://appshunter.io/ios/topics/hdr-max)

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-12.*